0:00  
Jim: Hello and welcome back to Plantopia. Plantopia is the plant health podcast of the American Phytopathological Society. And I'm your host, Jim Bradeen. I'm a professor of plant pathology and associate vice president at Colorado State University. And I'm really very excited about our conversation. Today, we're going to hear from Professor Gary Chastagner. Gary is a professor of plant pathology and an extension specialist in the Department of Plant Pathology at Washington State University, and he leads the ornamental plant pathology program. Gary is an expert on the diagnostics etiology, epidemiology, ecology and management of diseases and invasive pests, with an emphasis on ornamental nursery stock bulbs, cut flowers, Christmas trees and urban forests. Gary's research has also branched into climate change impacts on native plant health methods of community engagement in research, post harvest problems of Christmas trees and peonies, and technological issues impacting the export of trees and the importation of tree seed.

1:11  
Jim: Gary works with state and federal regulatory agencies to mitigate the impacts of Fatah forever moram. The pathogen that causes sudden oak death and impacts many different woody plant species. Gary is passionate about science outreach to growers and education through citizen science activities. Gary has been featured a lot in in popular press to give you a very short list. His work has been featured on the Discovery Channel, ABC, CBS, NBC, Fox, MSN, the CBS Morning Show, CBS national radio, NPR national radio Radio New Zealand, the New York Times, LA Times Chicago Tribune, USA Today, the Chronicle of Higher Education, Good Housekeeping, Men's Health, real simple magazine, and many, many other outlets. Gary is also a longtime APS member and has served on a variety of research committees. And as the APS Pacific Division counselor, Secretary, treasurer and President. And Gary has a large and very productive lab and a long, long list of publications. And today, we're going to talk specifically with Gary about his research and extension on Christmas trees. Gary, thank you so much for being on Plantopia. 

2:40  
Gary: My pleasure. 

2:34  
Jim: So we are really very delighted that you could take time to be with us to talk about Christmas trees. And to start off today, you mentioned something to me that that I think really sort of sets the scene here. It's the origin of your last name, which I pronounced Chastagner. Where does your name come from? And what does that mean?

2:53  
Gary: It's a French name. In our family, we call it chest egg or we say chest air, but I've been corrected when I've been in France. They pronounced shots lung yay. That means chestnut grower and so there's a region in France where there's a lot of chestnuts grown and and you'll see a number of Chastagners in that region as well as other areas. It is interesting in the US there's a group of Chastagners that uses the French pronounciation. And then there's a group of us that use an Americanized pronunciation.

3:29  
Jim: So you're a forest pathologist, an urban forest pathologist, did your name have any influence over your career choice?

3:37  
Gary: No, not necessarily. When I when I first went to college, I was fortunate enough to be able to go to college and stuff. And when I first went to college, I wanted to be an industrial arts teacher. And so I majored in industrial arts with a specialty in woodworking because I wanted to teach woodshop but I happen to have a biology teacher the first time I took a biology class and in a community college when I was a sophomore. And I, that biology teacher and Mr. Palmer was super good. And I was super interested in that class. And so when I went to Fresno State College in California, I decided to double major I asked questions about Well Could I double major one industrial arts because they had a good industrial arts program. That's the reason I went there. But they also had a good biology program and so I majored in got a double major and industrial arts and biology am intended to teach woodshop but when by the time I graduated in the early 70s, there were very few woodshop programs left in the United States because a liability issues. So I decided to see if I could go to graduate school.

5:00  
Jim: And you went to graduate school in plant pathology? How did you get from biology to plant pathology in particular,

5:06  
Gary: I grew up in Davis, California. And so I got some catalogs because I got the catalog at UC Davis. And I was leafing through it. And I saw plant physiology. And I really liked plant physiology when I was taking my biology undergraduate degree. And then I happened to flip a page and there was plant pathology. And I was reading about it. And I said, Oh, that sounds interesting. And some of it, I had worked at UC Davis, when I was in high school, in a clean peach breeding program that the university that I worked in that program for a number of years, through early when I was in community college, and stuff, but still lived in Davis. And so I said, Gee, plant pathology sounds really interesting. And so I wanted to talk to the graduate student visor, who happened to be at Butler, who was a mycologist, in the department. And he happened to have been one of my forage teachers when I was a young boy in four h. And so we were talking and he said something to the effect that, Gary, we've never admitted a student from Fresno State College, California State University of Fresno. And so we can, we can admit you, except you, you get really good grades. But we won't happen assistantships for you. I said, that's fine. I'll work and stuff. And so I started there, I sold hardware at Sears in Sacramento, and started there. And within a short period of time, I was offered an assistantship by Joe Ogawa, who is a tree fruit pathologist, and also did some work on tomatoes for a master's degree. And then when I completed that, he asked me what I'd be interested in staying on for a PhD. And I had no intention of getting a PhD. But he convinced me that I could do that and provided the support and the encouragement and stuff. And so I ended up working on fresh market tomato problems in California.

7:11  
Jim: That's quite a transition into this, this really amazing field. And I'm really fascinated by how people do get into plant pathology. There are a million different stories of how we discover this this incredible and in very diverse field. And how long have you been with Washington State University?

7:29  
Gary: So I was hired in 1978, started in March of 1978. And originally was hired to work on diseases of ornamental bug crops and turf grass. And it was a crazy sort of a position because I had turf grass responsibility for Idaho, Washington, and Oregon. And only money to support the work in. And so it was pretty crazy because I am plots. In general, I have a very applied plant pathology program trying to help growers solve disease management problems. And so I had plots in Oregon and Idaho, and in Washington that ends up and it was a lot of driving and things and, and so I'm not on the main campus. I'm at a research facility that's about 35 miles south of Seattle. And when I was hired, there was about 26 tenure track faculty here and maybe 120 people working here. And so it's been an excellent place to work.

8:39  
Jim: That's really wonderful. When did you get interested in Christmas trees? When When did that line of research start?

8:46  
Gary: Well, that happened because the Christmas tree industry in the northwest, which is a fairly significant size, they are having problems with a needle cast disease, an endemic needle cast disease that naturally occurred here on Douglas fir Christmas trees. And at that time, douglas fir accounted for probably about 90% of the trees produced in Oregon and Washington. And there was a lot of questions about how to manage that disease. It was causing premature casting of needles before harvest, and so the needles so you'd have trees that would not have sufficient needles that they could be cut and marketed against. So the recommendations at that time or multiple applications of fungicides during the growing season, very little information available. They WSU didn't have anyone working on Christmas trees at that time. The growers out of frustration went directly to the legislature. They said we would really need some help in managing this disease figuring out how to manage this disease. is. And so the legislature directed the university to find someone to work on Christmas trees. I was the new kid on the block in western Washington, where the Christmas tree is relocated. And by the way, the legislature didn't appropriate any additional money. They said, Okay, WSU, you need to take some money that you already have, and work. And so I think it was the only time that Dean's ever been in my office. And he came over one time on a trip over here and stopped by to talk to me and said, Gary, we've we've got an opportunity for you, if you want, are interested in work to work on Christmas trees, and oh, by the way, will will provide you a $30,000 over the next two years. To work on it. Well, $30,000 back then. And 1979 was more than it is today and, and stuff. And so I started working on Christmas trees at that time.

10:54  
Jim: And you've worked ever since on Christmas trees, amongst other things.

10:58  
Gary: Yeah, it's interesting how that we did a lot of work focusing on that 1980 Mount St. Helens blew up and covered my one of my major field trial with about a half inch ash. Wow, I was wondering, okay, am I going to survive? You know, okay, here's, I've got all my eggs in this one basket, if you will, as it relates to Christmas trees is, is, you know, all the work that we put in, and when they go down the drain, if you will, because of that, well, fortunately, it didn't. But we were able to solve that disease problem by identifying winds formulation, and releases force was what was occurring, a graduate student, Ellen Michaels did this work. And then we also, were able to identify very effective fungicides so that the growers could control the disease with a single application of a fungicide, when the new growth was about one to two inches in length. But it's interesting, Ellen when she was doing her work, we were looking at the amount of disease and trees in the Pacific Northwest. And an Oregon is the number one producer of Christmas trees in the nation. Washington is probably about fifth or sixth. But combined, these two states produce about 3% of the Christmas trees grown in the United States. And what Elon found in doing surveys to determine the impact of Swiss needle cast was that it was only causing enough needle loss to impact the quality of trees at harvest on about 15% of the infected trees. But over 80% of the trees being grown at that time, were infected by the fungal pathogen. And so because I've done so much postharvest work as in my graduate studies in my major professor was very involved in post divers where I wanted to know what the presence of those infected needles, sort of asymptomatic infected needles on the tree did to the post harvest quality of the trees. So we arranged to ship trees back to Davis, where I had some friends to set up a sort of a display thing. And then we displayed trees at Pew Allah. And what we found there is the presence of those infected needles caused the trees to dry out twice as fast and also increased needle loss. But there was a key observation at that point in time. We had no massive needle shedding or loss of green needles on any of the trees that were handled that they do. But some of the trees I think there were two trees that were shipped to be this. They basically shed green needles within about a week of being placed indoors. Well, those trees had dried more than any of the other trees. So that observation then triggered additional studies to look at how far you could dry a cut tree before you had adverse effects on the trees. And so that led to a whole series of studies where we identified critical threshold moisture levels of trees once they're cut, and as long as they don't dry below that. If you recut them, then they rehydrate and behave virtually the same as a fresh cut tree. And that allowed us to then look at the moisture loss throughout the whole production marketing chain and determine where and if there were problems as far as moisture loss on trees once they're cut before the consumer is getting them and aware that that problem is arising? Is it due to the early harvest? Is it new to shipping? Is it new to the display of the trees on the retail lots.

15:16  
Jim: So a lot of factors really go into this. It's not just getting that that cut trunk, that cut stem, into into water, necessarily it's, also humidity and exposure to wind or dry air. Probably a lot of factors that influence that, right?

15:37  
Gary: Yes, and you have the whole whole range of factors including the species of conifer that used as a Christmas tree, some can tolerate more grind than others. When it's harvested, what the environmental conditions are the storage areas where the inventory is being built up. What we have shown is that there's very little moisture loss on trees during transit and shipment. And we've done shipping trials to various places in the United States. And we don't see significant levels of moisture loss. During those shipping trials. We've even monitored the Capitol Christmas Tree, which is an 85 foot tall tree that various forests compete to, to donate that tree for use in Washington, DC. And we've had I've had students who worked on following the moisture content of that tree as it shipped across the United States. And, and that tree, of course, is very large and amazingly loses very little moisture, even though it takes about a month to get it across the tree. But us because it's they stop in various places and it's displayed and citizens come and Green School kids come and look at the tree and put the decorations on it on its way to Washington DC. Those are real fun project. But the moisture status changes in moisture status is is an important thing and maintaining that moisture status of the tree is the number one way of maintaining the quality of the tree and reducing needle shedding issues. If you start out with a healthy tree,

17:23  
Jim: You mentioned that this early work you did with Swiss needle cast was was on Douglas fir. You've also talked about sort of the diversity of different evergreen species that are used as Christmas trees. Give us an idea of what other species are involved and how this has changed throughout your career.

17:44  
Gary: So if you look at the historical perspective of production of Christmas trees, if you're in the northeastern part of the United States, balsam fir has been and continues to be a fairly significant species, but it's native to those areas up into Canada and things early on a lot of Spruce were grown. Scotch Pine was a very important species even when I first started working on Christmas trees 40 Some years ago. One of the reasons that spruce and Scotch Pine were so important is they would tolerate a lot of different growing conditions, they could grow in soils that were maybe marginal, or had too much moisture and stuff that other species would or would not thrive them. Douglas fir a was the principal species growing out here the coastal form of douglas fir, the inner mountain form of douglas Fir is grown in the Upper Midwest, and things it'll tolerate the cold temperatures. But the one of the major changes that occurred and really shifted the balance of what is being grown is that Fraser fir became a species that started to be grown in the 60s fairly widely in North Carolina. And now accounts for probably 90% of their Christmas tree industry is based on Fraser fir. And Fraser Fir is now considered to be one of the premium Christmas trees and it's actually grown in many areas Wisconsin, there's hardly any Scotch Pine left in Wisconsin, it was widely Scotch Pine was widely grown in Wisconsin, that's all been replaced by Fraser fir and stuff in the northwest, as I mentioned that was for was the principal species when I started in the late 70s Nobel for was just coming being looked at as a potential species. It's a high elevation species that's native To the Cascade Mountain ranges and stuff, so they bring it down to these lower elevations. And there's a lot of problems as far as terminal but abortion and environmental related issues and Subscene zone work was done and they identified sources of seed of noble for that performed well in Christmas tree sites. And so they started growing it, it now probably accounts for almost 45% of the production. And it has excellent moisture and needle retention characteristics. So if you look, Fraser fir and Nobel for the production of those two species have really displaced a lot of the less desirable species, such as some of the Scotch pine and many of the spruces in many areas. And so the quality of trees has increased tremendously. And the trend is to grow these true first members of the ABS genus as opposed to other species of conifers.

21:09  
Jim: And you mentioned seeds are actually don't know anything about how Christmas trees are produced are they grown from seed are they clonally propagated.

21:22  
Gary: Virtually all Christmas trees are grown from seed. And so there are a few seed orchards that's been established in the Pacific Northwest we have Douglas fir am available for a seed orchards their seed orchards and that are Fraser fir, particularly in North Carolina, there's still a lot of collection in native stands of these trees that have been tested over the years to produce progeny seed from those regions produce progeny that perform well as Christmas trees. And then we're doing more and more work on exotic species of the species that are such as Nordman Turkish, and more recently Trojan for these are species from around the Eurasia area around the Black Sea, Republican Georgia, Turkey, they have a number of potential advantages over some of our other species. They have some natural resistance to Balsam Woolly Adelgid, which was introduced into North America a number of years ago. And as a significant pest particularly a Fraser fir, as well as they have some tolerance and resistance to some of the fight offers that limit where Fraser and noble for can be grown. That's one of the things that we saw as a shift. When we started growing more and more of the like a noble for and Pacific Northwest and brasier for these species are extremely susceptible to fight off rare root rot. So if you have Phytophthora root rot introduced into the Christmas tree planting, usually via the movement of infected nursery stock. You can have significant problems if you have a site that has the soil moisture requirements that are favored, that need to be in there for a fight topper to develop. We've had some situations like when no buffer, there's another needle cast disease, we call it interior needle blight, different fungus than Swiss needle cast. Again, we've done a lot of work with those and have come up with similar controls like we have for this Swiss needle cast. So the growers are able to manage needle cast diseases fairly well. The once you have Phytophthora in a production site, it's very difficult to manage that disease, there are no chemicals that can really be used that are effective in a production site. So really, your choices are to abandon that site or shift to a less susceptible species. And that's why so much work is being done right now on some of these exotics from Europe, because they seem to have more tolerance to fight out for a rock.

24:20  
Jim: This is a really good transition into the next question I had for you and in one of your recent publications. This is published in plant disease. And your your co author, actually the lead author, I think was a former grad student Kathleen McKeever. 

24:39  
Gary: Yes. 

24:40  
Jim: This this manuscript is called "Interactions Between Root Rotting Phythophthora, Abies Christmas Trees, and Environment." What's this paper all about?

24:51  
Gary: So Katie's research really looked at the diversity of white tough rows in Christmas tree production areas across the United States. Often, growers might read a publication out of North Carolina. And most of their Phytophthora problems are associated with phytophagous. antimony. So the growers might read that and say, Okay, here's what they're finding. Well, we don't have I talk for a moment. Out here, we have different fight offers by topic came Deborah, for example. The Northeast doesn't have fight offers senemome. And so Katie tried to she did a study and collected material and identified the phyto offers that are most common throughout the US in major production regions. Then there was this question about why do we have maybe differences in we may see that something is tolerated out here a particular species is tolerant, we're dealing with a different environment, we don't have summer precipitation, to speak of, and, and we have a cooler temperature. And we have different fight conference. And so if you look at some data coming from North Carolina, versus let's say, the Pacific Northwest, we may see the North binfer works fairly well, we don't see very much disease on it at all. It's not, whereas in North Carolina, it's can be very susceptible in certain situations. And so her work was to look at the effect of temperature, soil temperatures and stuff on the susceptibility of some of the major species that are grown as Christmas trees. So what we did is, she was doing this, these trials of controlled greenhouses that involves a lot of work a lot of seedlings. And in trying to understand whether there's, if something's resistant at a cool temperature or tolerant at a cool temperature to this particular Phytophthora, is it also tolerant at a higher temperature, such as you might see, in North Carolina, what you found was that, in general, at cooler temperatures, overall, the cinema me I mean, the, the disease development on billable for and Fraser for was still quite high. But there were a number of species that had quite good tolerance under cool production conditions. At warm conditions, higher temperatures, that picture changed, there are much fewer species of conifers that were included in that trial that had good tolerance to, to the fight toughness that we were looking at, she looked at four species of Viton, for multiple isolates of each of these species. So that helps set some some ideas on Well, where can we recommend some of these species, they may work well, in Michigan, you know, or New York, or the Pacific Northwest, they don't work maybe as well in North Carolina, on because of a difference in Viton for species, and also because of warmer production conditions. So it helped clarify a lot of the variation, if you will, and what the previous reports were, and stuff as far as what species really may have some potential utility as a tolerant species to be grown in areas where you can't grow Fraser where you can't grow mobile fir.

28:50  
Jim: And what do studies tell us about climate change and you know, adaptation of this this industry?

28:57  
Gary: So there's two things. The study indicates that if we were to have warm, increasing temperatures, particularly of the soil and combined with increasing periods of saturated soil, we're going to end up with increasing potential for Phytophthora root disease problems, this may change. In other words, we may have a geographical region that normally doesn't have much of a photographer problem. But now we start getting prolonged periods of moisture saturated soils that are favorable for for photographer to develop. And so we potentially could sci fi tougher in those sites where in the past by tougher was not a significant issue. In the other situation if the soils are warmer, we're going to see an increase risk from Fight tougher and the damage from fight tougher. Because the fight offers will develop, the damage will be more severe. So climate change has the potential to change dramatically. The the areas where certain diseases are important, what diseases are important, even needle cast diseases they need generally for needle cast diseases most needle cast diseases, infection takes place shortly after, but break. But if you have new budbreak in an environment where you normally don't have continuous, drizzly rain, like we have in the Pacific Northwest in the spring, well, you're generally not going to have too much of a problem with a needle cast. But if the environment changes, and we end up with prolonged periods of cool moist weather, in the spring, in areas where it didn't occur previously, the needle cast diseases will become more important. The other thing that we do a lot of postharvest work on Christmas trees, particularly as it relates to needle retention, and needle loss. And I made some comments about Swiss needle cast and premature casting and moisture status. What happens is, for most a bee species and most Christmas tree species in general, and we've tested a large number of the commonly grown species, if you allow them to dry, a certain percentage of the trees will begin to shed green needles as early as three, but certainly seven to 10 days after they start to dry. They just will shut needles, you can touch the branch and the needles just fall off. That's influenced by the genetics of the tree, the host, which species of tree it is, and it's influenced by how dry you allow that tree to go. So what we've shown is that trees in general, needle retention improves the later you harvest that primarily because of increased accumulation of cold and Chilean hours in the fall and maybe shorter day lakes. But if we end up with climate effects on how cold it gets in the fall, or how cold the weather we have in the fall. And let's say it's a warm fall type of a situation well, we'll see increase damage to trees or in their quality, their post harvest quality, because they will not have as good a beetle retention ratio for as excellent needle retention, as long as it receives cold weather in the fall prior to harvest. If you have a warm fall in North Carolina, you get increasing reports of green shedding of needles even on the retail lot and stuff with that species, noble furs, the only species that we've tested, that doesn't seem to behave like that. And one of the things as a result of the work that we've done, we've identified a very simple detach branch test, I used to do work on hold trees are post Iris that a room was quite large, we would display whole trees may be 100 trees at a time. We have two very large temperature controlled rooms that we do all of our post harvest work in, I started out in an abandoned room with a Swiss needle cast. But we had an abandoned building. And so we turned the heat back on and I use that climbing up and down stairs hauling trees up and up to do our first post harvest trials. Now we have much better facilities, probably the best facilities of any place in the in North America and maybe Europe. So when we do those tests now, of course, when we would do a test them a tree, that tree is cut. And we can't repeat that test on that same tree year after year to see where we can't look at what would happen if we harvested this tree early versus late. So we developed a detach branch test that correlates very well with what you see with a whole tree. And that test has now been used by people across North America and Europe to look at the genetics and the genetic variation within trees. Look at the effect of the time of timing of when things are harvested. And we've been able to use that test to identify trees that really don't need cold acclimation that genetically just have superior Your needle retention. And a lot of that work has been done where it's doing that work, people in the genetics, people in North Carolina are doing that work on Fraser fir. And there's people in the University of Copenhagen that are doing a lot of work on Christmas trees in that area as well. So the development of that technique has allowed us to understand a lot of the variables that go into needle shedding, and have allowed us to identify individual trees and sources of trees that have excellent needle retention. And then of course, they have to have good growth characteristics and other attributes. But before we started doing our work, very little attention was paid to post harvest. All the seed orchards that were being established were just based on growth of needle color and needle length. Not considering anything about post nervous. Now, we have people air frating samples from trees and seed orchards wanting us to test those trees so that they can identify the individual trees in the seed orchard that have corneal retention, they cut those out, get rid of them. And we had a three year project in Denmark. And that showed that if the mother tree but the comb produce the comb, a good seal, needle retention, the progeny from that tree tend to have good needle retention. So this is a tremendous increase in our understanding of how we could improve the quality of trees simply by screening things in existing seed orchards, and calling out all the trees that had poor needle retention, a property, then from the next crop, a seed from that seed orchard would tend to have a much better needle retention than previously.

36:55  
Jim: That's really, it's really fascinating. And as somebody who's worked on plant genetics for most of his career, I really appreciate the the level of genetic variation you're describing in these plants and the strategy to really utilize those genetics to select for for the traits that make this product. So valuable, sort of opens another line of question that I'm curious about, is there a future for genetically modified Christmas trees or gene edited Christmas trees?

37:24  
Gary: Certainly there may be there's a, there's a relatively poor understanding actually, of the genetic mechanism of the specific genetics involved, we know that there's tremendous genetic variation in the trees, just like you have for budbreak. There's very little work, however, been done on that. One, because of, I think, one there not that many genetics, people were actually working on Christmas trees. You know, the Christmas tree research group is a relatively small group of people. And stuff. And in fact, one of the issues that I saw when I first started working on Christmas trees was that we really didn't have a good way of sharing information and talking amongst the researchers and extension people. So we hosted a meeting, I think, in 1988, or 1989, Christmas tree and international Christmas tree Research and Extension conference. At that time, it was people from British, Canada, and throughout the US that came to that that meeting has since grown, then we're now We just hoped that our we didn't host them. But in California, we just this last June was the 15th meeting of this group, this working group, that group, it's a small group, you know, we might have 40 people, 25, 40, depending on where it's held and stuff. That has resulted in a lot of collaborative efforts where I've worked with geneticists, you know, in North Carolina, I work with geneticists in Denmark, and stuff to begin to try and answer some of these things. The, there's a lot of, there's not that I'm aware of any specific effort currently underway to genetically modify abs. As for use as Christmas trees, I think there's some concern about you know, consumer acceptability, there's big time concern as it relates to forestry, you know, introducing genetically modified trees in a forest situation where you may have pollen, and what that might do. I don't think people are ready to have this happen, certainly in forestry. And that falls also in Christmas trees, whether gene editing, you know, some of the gene editing things would be more acceptable. That might be I think one of the other challenges So, as we do have this diversity of species that are grown, and the need to then the marketplace for Christmas trees, in many cases dependent upon consumers have preferences. And sometimes those are regional preferences. You know, their history is we've always bought this kind of a tree, we're looking for this tree. Now, they may not actually know, you know, in the northwest, they would say, Okay, we want a noble for, but the consumers generally aren't going to be able to tell a normal for from a Nordmann for and in some cases that can't tell them from a Fraser for but they know that they want a Nobel for example. And so there's an there would be a number of obstacles, I believe, you know, to to utilize sort of genetic modified plants in a Christmas tree situation, maybe those things will change. And if so, I think there's potentially a tremendous opportunity to deal with some of these things.

37:40  
Jim: It'll be interesting to see how this unfolds a lot of factors going to into Christmas tree.

41:15  
Gary: It is it is interesting. There are some trees, I'll use European silver for absl. As an example, it's not used as a Christmas tree. I had a colleague from Great Britain. He told me that if you were growing European silver for as a Christmas tree, and you walked out in the Christmas tree plantation with a chainsaw, all the needles and fall off the tree. He said, in history, we've grown that species here for some trials and things and I'd venture to say that if you cut and display that tree and allow it to dry 80% of the trees may not have any needles within 10 days. They just dropped needles like crazy. But the interesting thing is balsam fir historically has very important needle retention. That's one of the issues with balsam fir, historically, but we started doing some work on balsam fir with some collaborators in Nova Scotia from dig into balsam fir, they still grow some balsam fir as wild culture trees. In other words, historically, if you look at one of the changes in the Christmas tree industry, most Christmas trees now are grown on farms and plantations, seedlings are planted there, depending on where you are and what seed you know, it's going to take seven to 10 years. Once you plant the seedlings to get up a harvestable size Christmas tree, you know, six to seven foot tall Christmas tree. So what we did is in Nova Scotia, they leave trees in a forest that's been cut down, that are producing cone and shedding seeds into the environment and then they farm the wild seedlings that come up. So the harvest rates in those types of situations is pretty low 50 trees to the acre. But so we tested balsam fir from Nova Scotia using branches, they could airfreight them to us and we test these. What you see in some cases is you might find if you tested 100 samples from 100 trees, you might find three that don't shed needles. So we test this the next year. Because it may not be you know, maybe it was a year from the fall. We test it the next year. Well, there's clearly so what we generally do is when growers are interested in doing this and stuff, we usually test individual trees for a period of three to five years to identify ones that over that period of time have never exhibited any needle shedding. We do these tests in September to maximize our ability to identify trees that don't mean cold acclimation. Because if we if we waited and did these tests in December, or late November, generally what you'll see is a shift from maybe three to 5% of the trees have the desirable needle retention to look in in December, maybe 65%. That's not the time to test. The time to test is back here because that addresses the issue. If we do have warmer falls, then we are going to be producing stock that genetically has the ability to still have excellent needle retention and not stock that yes in December if it had cold and stuff, it has good needle retention. I am stuff, ethics. So even a species that has really core needle retention soon nificant improvements in the quality of that particular species can be made. And the fact then that we can identify in seed orchards. That's almost the immediate improvement in quality. And then we can also propagate sign wood from trees, the superior trees that we don't have and see orchards to produce, you know, second in new seed orchards. And a lot of that is going on currently. So the future is sort of bright, or significant improvements in the quality of Christmas trees that are available to consumers. And the consumers play a significant role, because our research in our trials have shown that the single most effective way you can flip a tree that has a tendency to have poor legal retention. If you make a fresh cut, and display that tree in water, and do not allow it to dry, those trees generally also have good needle retention. It's a matter of not allowing that tree to dry after it's been cut. So retail lot operators, we've done simulated retail lot trials, developing information on how retail operators can maintain the moisture of the trees on the retail lot by using micro misters. And stuff like this. And consumers have a significant role in improving the quality of their own trees by making sure they are properly caring for the tree wants us displayed in their home.

46:50  
Jim: Great. Well, do you have any parting comments for consumers? I guess, you know, a lot of the factors that you're describing really take place before the consumer ever comes into the picture. So what other advice would you have for how to select that perfect Christmas tree?

47:10  
Gary: Well, for consumers when they go to a retail lot, whether it's a big box store, a nursery, or you know, a traditional Christmas tree, I often get asked questions by reporters, what's the perfect Christmas tree or what is a perfect Christmas tree...

47:29  
I purposely didn't ask you that question. 

47:32  
Okay, when I tell him it's all in the eyes of the beholder, because there are some who want to Charlie Brown one sided tree or whatever the issue is, but everyone needs to whether they're getting a inexpensive tree, or they're paying $300 $600 For that tree, at some places. That's what trees, large trees cost. They deserve a tree that has the ability to maintain needles, and freshness. And consumers can do a lot when they go to buy a tree. Look at the tree closely, that they're looking at, to considering to buy, tap the base of the tree. There should not be any green needles that fall off of the tree. Sometimes there'll be old dead beetles on the inside, those will fall off, they're brown, the grower or the person who's selling you the tree, they should be able to shake the tree, they have mechanical shakers in many places, and all those will come out. And when they take that tree, make a fresh cut on the base and display it in water. What most people do not realize is how much water a tree utilizes. And we have a general rule that for every inch of STEM diameter. On the trunk, you need a stand that holds a quart of water. So if you take a stem that's four inches in diameter, you need to stay on that holds one gallon of water, you need to check it every day. Most of the water use is going to be initially but the ABS species will continue to take water up, we're able to display trees and wait degrees centigrade or 68 degrees Fahrenheit, which is our traditional test on some of our best species, were able to maintain those trees in there for the longest we've done it's three months, they actually break bud and think that they're gonna grow again, even though they have no roots. But it's not a problem to maintain some of those species, you know, for an extended period of time. The other things that consumers need to ask is, if I'm buying a tree, and I only want it to last one week, I have lots of options. If I'm buying a tree and I want it to last six weeks, there's much fewer options. Some species such as as coastal Douglas fir grand for some of these other species, their their limit even displayed in water is about four weeks. Whereas this is one of the reasons the AB species that becomes so important is you can go much longer with those if they're properly cared for. The temperature of the water is not important. You don't need to add water additives or anything like this just pure water. It's making sure that that base is a fresh cup and continually displayed in water and and then if you do see the tree, eventually all trees will dry. Make sure and remove that tree because potentially the trees if they're allowed to dry, improperly cared for and they're exposed to it and ignition source that can be a significant fire. 

50:50  
Jim: That's really great advice. Gary, it's been an absolute pleasure talking with you today appreciate you being our host, our guest on Plantopia podcast.

51:01  
Gary: My pleasure, Jim.

51:02  
Jim: We just heard from Professor Gary Chastanger from Washington State University telling us about his plant pathology research on Christmas trees. Thank you for joining this episode of Plantopia podcast. We will see you next time.

Transcribed by https://otter.ai