1 00:00:05,900 --> 00:00:07,660 - Jeff Ward is the Chief Scientist 2 00:00:07,660 --> 00:00:10,610 with the Department of Forestry and Horticulture 3 00:00:10,610 --> 00:00:13,510 at the Connecticut Agricultural Experiment Station 4 00:00:13,510 --> 00:00:17,040 and, today, is presenting "Multiyear Defoliations 5 00:00:17,040 --> 00:00:20,420 in Southern New England Increases Oak Mortality". 6 00:00:20,420 --> 00:00:22,160 Jeff, take it away. 7 00:00:22,160 --> 00:00:24,540 - So yeah, I'm gonna be talking about some research 8 00:00:24,540 --> 00:00:26,510 we started before we joined FEMC, 9 00:00:27,380 --> 00:00:30,650 but I think it's really gonna highlight the importance 10 00:00:30,650 --> 00:00:34,540 of longterm monitoring, policy monitoring long-term time. 11 00:00:34,540 --> 00:00:36,330 I can end up looking at questions 12 00:00:36,330 --> 00:00:38,960 you've probably never even thought of when you set it up. 13 00:00:38,960 --> 00:00:42,500 And if you've never seen severe gypsy moths defoliation, 14 00:00:42,500 --> 00:00:45,960 that was a stand last year in Western Connecticut 15 00:00:45,960 --> 00:00:48,260 and that picture was taken at the end of June. 16 00:00:49,920 --> 00:00:52,000 So at the very beginning, I just want to thank 17 00:00:52,000 --> 00:00:55,370 all of our great partners in setting up this study 18 00:00:55,370 --> 00:00:58,000 and, especially, Alenka Mora and Sarah Sullivan, 19 00:00:58,000 --> 00:00:59,430 we'll close a lot of field work, 20 00:00:59,430 --> 00:01:01,453 and my right hand, JP Barsky. 21 00:01:03,130 --> 00:01:05,458 So here's the take home message. 22 00:01:05,458 --> 00:01:07,100 I like putting up the beginning. 23 00:01:07,100 --> 00:01:09,590 First of all, multi-year defoliation events 24 00:01:09,590 --> 00:01:11,740 are really important, where you're gonna see, 25 00:01:11,740 --> 00:01:13,050 as far as oaks, is you're gonna see 26 00:01:13,050 --> 00:01:14,620 the loss of lower canopy oaks, 27 00:01:14,620 --> 00:01:17,390 you're gonna see the loss of white oaks, 28 00:01:17,390 --> 00:01:20,700 and you're gonna see the loss of low vigor red oaks 29 00:01:20,700 --> 00:01:23,430 and there's a new thing that we found recently. 30 00:01:23,430 --> 00:01:25,090 I'll try to get that to the end. 31 00:01:25,090 --> 00:01:27,530 So what was our previous knowledge about that? 32 00:01:27,530 --> 00:01:30,010 Well, we actually set up, our oldest research plots 33 00:01:30,010 --> 00:01:33,880 go back to 1927 that we measure every 10 years. 34 00:01:33,880 --> 00:01:37,190 So we're able to measure ingrowth, death mortality, 35 00:01:37,190 --> 00:01:41,461 and then when we have an event happen, like defoliation, 36 00:01:41,461 --> 00:01:44,740 we're able to see what the impact of that is on the forest 37 00:01:44,740 --> 00:01:46,460 and was fortunate on this forest 38 00:01:48,570 --> 00:01:50,840 is or unfortunate, I should say, 39 00:01:50,840 --> 00:01:52,690 is there's some pretty severe defoliation. 40 00:01:52,690 --> 00:01:55,270 We had three years of, you know, 41 00:01:55,270 --> 00:01:58,430 40% or more defoliation back in the '60s, 42 00:01:58,430 --> 00:02:00,490 two years in the '70s, and one year 43 00:02:00,490 --> 00:02:03,093 of big defoliation back to the 1980s. 44 00:02:04,900 --> 00:02:06,737 And one of the take-home message, if you look in the bottom, 45 00:02:06,737 --> 00:02:09,410 you can see the measurement period we had 46 00:02:09,410 --> 00:02:11,600 and if you look in the side, 47 00:02:11,600 --> 00:02:13,700 that's mortality of upper canopy oaks 48 00:02:13,700 --> 00:02:15,470 and notice, that only goes up to 40%. 49 00:02:15,470 --> 00:02:17,540 I'll explain why in a second. 50 00:02:17,540 --> 00:02:18,840 But we had three years, 51 00:02:18,840 --> 00:02:21,400 three years of repeated defoliation. 52 00:02:21,400 --> 00:02:26,400 We saw that we had close to 35% of all oak trees died 53 00:02:27,050 --> 00:02:29,180 for repeated defoliation. 54 00:02:29,180 --> 00:02:31,120 With two years of defoliation 55 00:02:31,120 --> 00:02:36,120 back in the '60s through the mid '70s, we had around 50% 56 00:02:37,420 --> 00:02:39,190 and then with one year defoliation, 57 00:02:39,190 --> 00:02:43,310 the oaks really can tolerate one year defoliation 58 00:02:43,310 --> 00:02:45,460 and the periods without defoliation, 59 00:02:45,460 --> 00:02:47,190 upper canopy oaks we had, you know, 60 00:02:47,190 --> 00:02:49,783 less than 1% mortality on average. 61 00:02:52,140 --> 00:02:54,573 Compare this to the upper canopy oaks. 62 00:02:56,077 --> 00:02:59,540 Compare the lower canopy oaks, the upper canopy oaks. 63 00:02:59,540 --> 00:03:01,900 Lower canopy oaks, those trees are already stressed 64 00:03:01,900 --> 00:03:04,420 because they aren't getting as much sunlight, 65 00:03:04,420 --> 00:03:06,310 much, much higher mortality. 66 00:03:06,310 --> 00:03:09,460 In fact, the first period we had, 67 00:03:09,460 --> 00:03:14,070 the first multi-year period we had back in the mid '60s, 68 00:03:14,070 --> 00:03:17,320 we lost over 85% of the lower canopy oaks 69 00:03:17,320 --> 00:03:20,910 were killed by the defoliation induced mortality. 70 00:03:20,910 --> 00:03:22,550 And even when we only had two years, 71 00:03:22,550 --> 00:03:24,390 we still had close to half of those 72 00:03:24,390 --> 00:03:26,773 trees that survived then died. 73 00:03:27,780 --> 00:03:30,460 So that's one of the big things there. 74 00:03:30,460 --> 00:03:31,990 And commonly, as Judy said 75 00:03:31,990 --> 00:03:33,530 if you're in the earlier session, 76 00:03:33,530 --> 00:03:36,090 gypsy moths, by themselves, don't kill the oak, 77 00:03:36,090 --> 00:03:38,420 but they start to decline spiral 78 00:03:38,420 --> 00:03:40,490 where you can get on malaria root rot, 79 00:03:40,490 --> 00:03:42,220 two-lined chestnut borer, 80 00:03:42,220 --> 00:03:44,363 and, eventually, the oak tree dies. 81 00:03:46,620 --> 00:03:47,570 Oops, (indistinct). 82 00:03:48,838 --> 00:03:51,230 One of the things we also found from that earlier study 83 00:03:51,230 --> 00:03:54,060 is that white oak mortality was much higher. 84 00:03:54,060 --> 00:03:56,250 The white oaks, white chestnut oak, 85 00:03:56,250 --> 00:03:58,260 mortality is much higher than for the red oaks, 86 00:03:58,260 --> 00:04:00,760 for northern red, black, and scarlet. 87 00:04:00,760 --> 00:04:04,657 And mortality was also a higher per codominant oaks 88 00:04:04,657 --> 00:04:06,240 than they were for dominant oaks. 89 00:04:06,240 --> 00:04:08,993 So if were a red oak, even with repeated, 90 00:04:10,150 --> 00:04:11,402 you know, defoliation, 91 00:04:11,402 --> 00:04:13,070 if you were in the dominant crown class, 92 00:04:13,070 --> 00:04:15,580 you only had about 10% mortality, 93 00:04:15,580 --> 00:04:17,100 but then if you look at codominance, 94 00:04:17,100 --> 00:04:19,210 now we're getting up to 40%. 95 00:04:19,210 --> 00:04:21,263 So there's a real, you know, 96 00:04:22,870 --> 00:04:24,680 a real difference between crown classes 97 00:04:24,680 --> 00:04:26,600 because trees which are up in the sunlight 98 00:04:26,600 --> 00:04:27,780 are, generally, able to produce 99 00:04:27,780 --> 00:04:30,890 more carbohydrates so they have greater starch reserves 100 00:04:30,890 --> 00:04:33,970 to be able to refoliate after oak. 101 00:04:33,970 --> 00:04:37,263 I'm sorry, after gypsy moth defoliation. 102 00:04:38,200 --> 00:04:39,390 One of the other things we found 103 00:04:39,390 --> 00:04:42,253 is that faster growing trees, back then, 104 00:04:43,490 --> 00:04:45,710 the faster tree grooves, the more likely it was 105 00:04:45,710 --> 00:04:49,110 to be able to survive repeated defoliation. 106 00:04:49,110 --> 00:04:51,690 This held for the dominance, the red triangles, 107 00:04:51,690 --> 00:04:55,120 for the codominance, the orange triangles, 108 00:04:55,120 --> 00:04:56,530 and, also, for intermediate, 109 00:04:56,530 --> 00:04:59,440 so long as they had at least a 10th of an inch 110 00:04:59,440 --> 00:05:02,713 in diameter growth on average every year. 111 00:05:05,530 --> 00:05:07,350 So the first bottom line from that study 112 00:05:07,350 --> 00:05:09,253 is that multi-year defoliation 113 00:05:09,253 --> 00:05:11,320 has removed the lower canopy oaks. 114 00:05:11,320 --> 00:05:12,850 They remove less vigorous oaks, 115 00:05:12,850 --> 00:05:14,270 the ones that are growing slower 116 00:05:14,270 --> 00:05:16,033 and especially removed white oaks. 117 00:05:17,030 --> 00:05:18,830 One thing we did see back there, 118 00:05:18,830 --> 00:05:21,600 for time, I wasn't gonna go into this. 119 00:05:21,600 --> 00:05:25,300 Surviving trees did recover and 20 years later, 120 00:05:25,300 --> 00:05:26,880 we really didn't see that 121 00:05:28,220 --> 00:05:31,260 they had higher mortality over time. 122 00:05:31,260 --> 00:05:33,473 So those who survived were able to do well. 123 00:05:35,490 --> 00:05:37,320 And then we went through a 30-year period 124 00:05:37,320 --> 00:05:39,380 without a major outbreak 125 00:05:39,380 --> 00:05:42,150 and this was actually right after, 126 00:05:42,150 --> 00:05:43,390 the last big defoliation 127 00:05:43,390 --> 00:05:46,860 was right after I came here in the late '80s. 128 00:05:46,860 --> 00:05:51,013 So most of foresters are really put worrying about LDD 129 00:05:52,120 --> 00:05:54,670 and that's what the new name is for gypsy moth. 130 00:05:54,670 --> 00:05:57,050 It's now, I can never pronounce that, 131 00:05:57,050 --> 00:05:58,650 so you can read it down there, 132 00:05:58,650 --> 00:06:00,650 but really nobody worried about it, 133 00:06:00,650 --> 00:06:02,103 but wouldn't you know it, 134 00:06:04,230 --> 00:06:07,080 we had the hungry, hungry caterpillars came back 135 00:06:10,810 --> 00:06:13,740 and they just completely defoliated 136 00:06:13,740 --> 00:06:16,570 thousands and thousands and thousands of acres, 137 00:06:16,570 --> 00:06:19,590 especially in Connecticut, Rhode Island, 138 00:06:19,590 --> 00:06:22,470 and Eastern Massachusetts. 139 00:06:22,470 --> 00:06:26,490 And here's a map that was produced by the US Forest Service, 140 00:06:26,490 --> 00:06:28,390 where you can see just how extensive 141 00:06:28,390 --> 00:06:31,750 all the defoliation was and if you look at the areas 142 00:06:31,750 --> 00:06:34,760 that are sort of a deep, dark red color there, 143 00:06:34,760 --> 00:06:38,070 those were areas, I'm sorry, the red areas were, 144 00:06:38,070 --> 00:06:40,720 brighter red, were areas that had two years in a row 145 00:06:40,720 --> 00:06:43,880 repeated defoliations and we had some stands 146 00:06:43,880 --> 00:06:45,920 in Connecticut, at least, so we had three years 147 00:06:45,920 --> 00:06:47,580 of repeated defoliation. 148 00:06:47,580 --> 00:06:49,543 So those trees really got hammered. 149 00:06:50,920 --> 00:06:52,970 It was also compounded by something else 150 00:06:52,970 --> 00:06:54,610 is going on at the same time. 151 00:06:54,610 --> 00:06:57,260 Similar to back in the 1960s, 152 00:06:57,260 --> 00:06:59,500 we had an extended period of drought. 153 00:06:59,500 --> 00:07:03,420 If you look back in the '60s, there were four years straight 154 00:07:03,420 --> 00:07:07,280 when we had pretty severe drought characteristics 155 00:07:07,280 --> 00:07:09,020 during the growing season. 156 00:07:09,020 --> 00:07:13,840 If you look at what we had back between 1915 and 1918, 157 00:07:13,840 --> 00:07:17,750 we had, again, four years in a row where we had 158 00:07:17,750 --> 00:07:21,010 pretty moderate to severe drought situations 159 00:07:21,010 --> 00:07:22,310 during growing season. 160 00:07:22,310 --> 00:07:26,800 So the trees were hit with a one, two hammer. 161 00:07:26,800 --> 00:07:29,220 They were hit with both the drought, which weaken them, 162 00:07:29,220 --> 00:07:31,563 and then they were hit by defoliators. 163 00:07:33,020 --> 00:07:34,210 So in response to this, 164 00:07:34,210 --> 00:07:37,770 because the trees now are also 30 years older 165 00:07:37,770 --> 00:07:39,210 and trees are like people. 166 00:07:39,210 --> 00:07:42,960 They do have a lifespan and a lot of our oaks, 167 00:07:42,960 --> 00:07:44,320 the scarlet and black oaks, 168 00:07:44,320 --> 00:07:47,410 are probably getting towards late middle age. 169 00:07:47,410 --> 00:07:49,480 And just like a lot of us of a certain age, 170 00:07:49,480 --> 00:07:54,480 we're not quite as resistant to insects and disease. 171 00:07:54,520 --> 00:07:57,380 Well, not insects and diseases, but for us diseases, 172 00:07:57,380 --> 00:07:59,640 and are more likely to have issues. 173 00:07:59,640 --> 00:08:04,640 So we set up 29 study areas and we look at over 3,000 oaks 174 00:08:06,600 --> 00:08:09,220 and on all of these study areas, the ones we chose, 175 00:08:09,220 --> 00:08:11,960 these were areas where we had 10 years data 176 00:08:11,960 --> 00:08:14,323 prior to the defoliation outbreaks. 177 00:08:15,850 --> 00:08:18,330 So I want you to recall that we've talked about before. 178 00:08:18,330 --> 00:08:20,050 I didn't show you this exact graph, 179 00:08:20,050 --> 00:08:22,270 but we look at mortality of the red oaks, 180 00:08:22,270 --> 00:08:26,470 the red triangles, and the white oaks, the the blue circles, 181 00:08:26,470 --> 00:08:29,380 back during the '60s and '70s, 182 00:08:29,380 --> 00:08:32,350 white oak tended to have much higher mortality 183 00:08:32,350 --> 00:08:33,653 than the red oak did. 184 00:08:35,900 --> 00:08:39,270 Well, we did the preliminary one analysis. 185 00:08:39,270 --> 00:08:40,860 We found that, "Hey, something's different." 186 00:08:40,860 --> 00:08:42,500 Also the red oaks are dying 187 00:08:42,500 --> 00:08:44,850 almost at the same rate as the white oaks. 188 00:08:44,850 --> 00:08:47,640 Like I said before, we're speculating right now, 189 00:08:47,640 --> 00:08:49,230 but we think one of the differences 190 00:08:49,230 --> 00:08:51,593 are these trees are getting older. 191 00:08:53,300 --> 00:08:54,133 It's kind of interesting. 192 00:08:54,133 --> 00:08:56,620 A side note back in the 1930s, 193 00:08:56,620 --> 00:09:00,650 when they did a study of LDD and mortality, 194 00:09:00,650 --> 00:09:03,900 they called that part of Eastern Connecticut, 195 00:09:03,900 --> 00:09:06,840 Western Rhode Island, they called them gypsy moth proof, 196 00:09:06,840 --> 00:09:08,980 even though there's 50 moth going through there, 197 00:09:08,980 --> 00:09:10,720 they didn't see trees die. 198 00:09:10,720 --> 00:09:14,390 The difference was those trees were 90 years younger 199 00:09:14,390 --> 00:09:17,453 back in the 1930s when they looked at that data. 200 00:09:18,900 --> 00:09:22,060 The one thing we did find is that, again, 201 00:09:22,060 --> 00:09:25,760 the more defoliation hit, the more severe it was 202 00:09:25,760 --> 00:09:27,710 and persevere, we said it had to have 203 00:09:27,710 --> 00:09:29,423 at least two years of defoliation, 204 00:09:30,450 --> 00:09:33,223 you saw much higher mortality levels. 205 00:09:34,620 --> 00:09:36,830 And I said, blackouts, especially, 206 00:09:36,830 --> 00:09:38,580 are probably getting towards, you know, 207 00:09:38,580 --> 00:09:41,330 late middle age, early senescence 208 00:09:41,330 --> 00:09:44,570 so it became much more susceptible to defoliator, 209 00:09:44,570 --> 00:09:47,130 which deployed some at the exact wrong time of the year, 210 00:09:47,130 --> 00:09:49,300 right in the spring, right when they're using 211 00:09:49,300 --> 00:09:52,380 all of their stored energy to produce those new leaves. 212 00:09:52,380 --> 00:09:54,190 Now they have to pull on their reserves 213 00:09:54,190 --> 00:09:55,990 and if they don't have the reserves, 214 00:09:55,990 --> 00:09:59,023 they aren't gonna be able to recover as quite as well. 215 00:10:00,000 --> 00:10:01,370 And this is just a screenshot. 216 00:10:01,370 --> 00:10:04,520 This has taken two years after defoliation ended. 217 00:10:04,520 --> 00:10:06,600 And you could see this one here flying around 218 00:10:06,600 --> 00:10:09,260 thousands and thousands of acres of dead oaks. 219 00:10:09,260 --> 00:10:11,980 Those aren't defoliated oaks, those are dead oaks 220 00:10:11,980 --> 00:10:14,213 because the defoliation period had ended. 221 00:10:15,810 --> 00:10:19,580 So how do the stands recover, crystal ball? 222 00:10:19,580 --> 00:10:21,290 Well, the one thing we found in the past, 223 00:10:21,290 --> 00:10:23,350 just a little drawing, showing that 224 00:10:25,503 --> 00:10:27,390 whenever you look at a stump, 225 00:10:27,390 --> 00:10:30,730 you can see the trees really had slow growth 226 00:10:30,730 --> 00:10:33,210 during those periods, gypsy moth defoliations, 227 00:10:33,210 --> 00:10:36,000 as you would expect because now they have to use 228 00:10:36,000 --> 00:10:37,750 all their starch reserves not to grow, 229 00:10:37,750 --> 00:10:39,640 but to try to produce new leaves 230 00:10:39,640 --> 00:10:41,670 and new buds for the following year, 231 00:10:41,670 --> 00:10:45,200 but then they recovered and we saw pretty wide growth rings. 232 00:10:45,200 --> 00:10:47,470 But again, those trees were 30 years older. 233 00:10:47,470 --> 00:10:49,030 So what's gonna happen in the future? 234 00:10:49,030 --> 00:10:50,603 We're really not quite sure. 235 00:10:51,570 --> 00:10:53,820 The other thing we saw in the past, 236 00:10:53,820 --> 00:10:57,810 it was we saw a real upsurge, a real surge, 237 00:10:57,810 --> 00:11:00,990 in the growth of, down our way, it's mostly red maple, 238 00:11:00,990 --> 00:11:03,910 was some sugar maple, and especially black birch 239 00:11:03,910 --> 00:11:06,873 coming into these stands where the overstory oak had died. 240 00:11:07,933 --> 00:11:10,190 There weren't as many beech coming in, 241 00:11:10,190 --> 00:11:12,470 'cause we didn't have this many beech at the beginning, 242 00:11:12,470 --> 00:11:15,300 but over the last 30 years, beech had increased. 243 00:11:15,300 --> 00:11:17,700 And as Judy has said in the previous talk, 244 00:11:17,700 --> 00:11:19,220 we have a new bugaboo out there. 245 00:11:19,220 --> 00:11:20,730 We really don't know what's gonna happen 246 00:11:20,730 --> 00:11:22,800 because of beech leaf disease. 247 00:11:22,800 --> 00:11:24,860 In this past year, I saw several stands 248 00:11:24,860 --> 00:11:27,740 where all the understory beech were dead 249 00:11:27,740 --> 00:11:29,180 and in some of the stands, 250 00:11:29,180 --> 00:11:33,960 25% of the overstory beech had died in one year. 251 00:11:33,960 --> 00:11:36,060 So that's a very scary disease. 252 00:11:36,060 --> 00:11:37,240 Maybe the only good thing, 253 00:11:37,240 --> 00:11:39,030 I don't know if it's because of climate 254 00:11:39,030 --> 00:11:41,360 or weather or just pure luck, 255 00:11:41,360 --> 00:11:42,720 but it seemed to be restricted 256 00:11:42,720 --> 00:11:46,193 to within 30, 40 miles of Long Island Sound. 257 00:11:47,640 --> 00:11:48,750 The other thing to note, too, 258 00:11:48,750 --> 00:11:50,900 is when we saw the recovery in the past, 259 00:11:50,900 --> 00:11:53,370 this is before deer density was high 260 00:11:53,370 --> 00:11:55,840 and before the days this species became an issue 261 00:11:55,840 --> 00:11:58,970 and invasive species, I mean, Japanese barberry, 262 00:11:58,970 --> 00:12:02,590 multiflora rose, stiltgrass, bittersweet, 263 00:12:02,590 --> 00:12:04,120 these are all having a real impact 264 00:12:04,120 --> 00:12:06,770 on how these forests are gonna recover going forward. 265 00:12:07,780 --> 00:12:10,670 So the second bottom line, as we saw before, 266 00:12:10,670 --> 00:12:14,370 multi-year defoliations remove the less vigorous oaks. 267 00:12:14,370 --> 00:12:16,480 They remove lower canopy oaks 268 00:12:16,480 --> 00:12:18,650 and they remove the white oaks, 269 00:12:18,650 --> 00:12:20,210 but because the trees are older now, 270 00:12:20,210 --> 00:12:23,210 we're seeing increased mortality of red oaks 271 00:12:23,210 --> 00:12:26,593 and, unfortunately, I think that's gonna be likely the norm. 272 00:12:28,210 --> 00:12:31,090 And as I said, surviving trees recovered well in the past. 273 00:12:31,090 --> 00:12:34,420 How are they gonna do going forward as they're older? 274 00:12:34,420 --> 00:12:36,340 We just don't know. 275 00:12:36,340 --> 00:12:37,570 And the one thing you can see 276 00:12:37,570 --> 00:12:41,230 is defoliation induced mortality. 277 00:12:41,230 --> 00:12:43,350 Mortality comes after defoliation, 278 00:12:43,350 --> 00:12:44,800 whereby defoliation 279 00:12:45,657 --> 00:12:49,790 can increase in succession of maple and birch down our way 280 00:12:49,790 --> 00:12:51,280 and probably beech. 281 00:12:51,280 --> 00:12:52,160 Now, you might be thinking, 282 00:12:52,160 --> 00:12:54,390 those of you who are up further North, 283 00:12:54,390 --> 00:12:57,000 well, you don't have to worry as much about gypsy moth. 284 00:12:57,000 --> 00:12:59,830 But gypsy moth likes to feed on an oak, 285 00:12:59,830 --> 00:13:02,340 but it also loves aspen and I know aspen 286 00:13:02,340 --> 00:13:04,573 is the species we're trying to maintain, 287 00:13:05,820 --> 00:13:07,200 not so much for timber value, 288 00:13:07,200 --> 00:13:10,920 but because it has some real important wildlife values 289 00:13:10,920 --> 00:13:13,343 and gypsy moth love aspen. 290 00:13:15,660 --> 00:13:18,020 So with that, I'm gonna stop sharing my screen 291 00:13:18,020 --> 00:13:19,840 and if anyone has any questions, 292 00:13:19,840 --> 00:13:23,660 be more than happy to answer you. 293 00:13:23,660 --> 00:13:26,320 - [Judy] We do have a couple of questions in the chat box. 294 00:13:26,320 --> 00:13:27,153 - Sure. 295 00:13:28,490 --> 00:13:31,010 - [Judy] The first one, "Can we comment on the potential 296 00:13:31,010 --> 00:13:34,827 for prescribed fire as a tool for encouraging oak region?" 297 00:13:35,695 --> 00:13:36,670 (laughs) 298 00:13:36,670 --> 00:13:38,560 - That's a little off subject. 299 00:13:38,560 --> 00:13:41,810 Prescribed fire, I think would work pretty well, 300 00:13:41,810 --> 00:13:45,060 but you're gonna have to have repeated prescribed fires. 301 00:13:45,060 --> 00:13:47,740 Reason why we can't really use prescribed fire 302 00:13:47,740 --> 00:13:49,420 as a tool down here in Connecticut 303 00:13:49,420 --> 00:13:50,803 is because of air quality. 304 00:13:51,970 --> 00:13:54,870 We're just very much an urbanized state. 305 00:13:54,870 --> 00:13:57,820 Even though we're close to 60% forest cover, 306 00:13:57,820 --> 00:13:59,210 we also are the fourth, 307 00:13:59,210 --> 00:14:01,563 most densely populated state in the country. 308 00:14:02,540 --> 00:14:05,883 So that's really a tool that's not in our toolbox anymore. 309 00:14:07,736 --> 00:14:09,397 - [Judy] Another question in the chat box. 310 00:14:09,397 --> 00:14:11,120 "What do you think the mechanism 311 00:14:11,120 --> 00:14:13,160 is underlying the greater vulnerability 312 00:14:13,160 --> 00:14:15,007 of older red oak trees?" 313 00:14:16,284 --> 00:14:17,983 - Ah, boy, I wish I could answer that. 314 00:14:17,983 --> 00:14:20,210 I'm not a tree physiologist. 315 00:14:20,210 --> 00:14:25,210 I think part of it is as the trees get older, 316 00:14:25,830 --> 00:14:27,683 they have to support a lot of, 317 00:14:28,630 --> 00:14:31,840 you know, tissues on the branches and on the trunks 318 00:14:31,840 --> 00:14:35,560 and those are nonproductive tissues so they, 319 00:14:38,540 --> 00:14:40,900 you know, they're, I don't want to say they're parasites 320 00:14:40,900 --> 00:14:43,660 because they're holding up the leaves, 321 00:14:43,660 --> 00:14:45,720 but, you know, when you start getting 322 00:14:45,720 --> 00:14:48,550 bigger and bigger branches, it takes more and more energy 323 00:14:48,550 --> 00:14:50,540 just to maintain those branches 324 00:14:52,540 --> 00:14:53,823 and the trunk space. 325 00:14:54,900 --> 00:14:57,730 And there's probably some other physiological reasons, 326 00:14:57,730 --> 00:14:59,370 but like I said, I'm not a physiologist 327 00:14:59,370 --> 00:15:01,203 so I don't know how to answer that. 328 00:15:03,470 --> 00:15:04,303 - [Judy] Okay, thank you. 329 00:15:04,303 --> 00:15:07,007 There's a couple more in the chat box. 330 00:15:07,007 --> 00:15:10,720 "I noted you used PDI in our FH reports 331 00:15:10,720 --> 00:15:15,570 and Vermont's Drought Monitor product is often referenced. 332 00:15:15,570 --> 00:15:18,200 What are people's favorite tools for looking at 333 00:15:18,200 --> 00:15:20,730 and quantifying drought as it relates to tree 334 00:15:20,730 --> 00:15:22,230 and forest health?" 335 00:15:22,230 --> 00:15:25,620 - Well, I'm gonna look at some of the modern parts, 336 00:15:25,620 --> 00:15:26,690 you know, I'm an old timer. 337 00:15:26,690 --> 00:15:29,520 So I still use the Palmer Drought Index. 338 00:15:29,520 --> 00:15:31,383 I like looking at the growing season. 339 00:15:32,568 --> 00:15:34,410 The reason why I look at growing season 340 00:15:34,410 --> 00:15:36,993 and not overall during the year is, 341 00:15:38,200 --> 00:15:39,660 as far as I've known, 342 00:15:39,660 --> 00:15:42,700 every year, the soils become completely recharged 343 00:15:42,700 --> 00:15:45,300 with moisture over the winter because you don't have 344 00:15:46,160 --> 00:15:48,440 the leaves pulling all the moisture out of the ground 345 00:15:48,440 --> 00:15:49,850 that we get enough snow and rain 346 00:15:49,850 --> 00:15:52,390 and soil moisture fully recharges. 347 00:15:52,390 --> 00:15:54,600 So I like looking at, you know, 348 00:15:54,600 --> 00:15:58,223 the drought during the actual growing season. 349 00:16:00,460 --> 00:16:02,120 So there's a question I can, 350 00:16:02,120 --> 00:16:03,330 actually, I can start reading now. 351 00:16:03,330 --> 00:16:05,937 Jeff Foran asked for one about, 352 00:16:05,937 --> 00:16:08,380 "Why the higher mortality for white oak?" 353 00:16:08,380 --> 00:16:12,730 I think part of it is LDD preference. 354 00:16:12,730 --> 00:16:15,750 Why does some of them have as many tannins in their leaves? 355 00:16:15,750 --> 00:16:17,073 And gypsy moths, 356 00:16:19,020 --> 00:16:21,930 you know, the tannins in leaves are primarily 357 00:16:21,930 --> 00:16:25,740 a defense against insect herbivory. 358 00:16:25,740 --> 00:16:29,700 So the gypsy moth, preferentially, where I've seen it, 359 00:16:29,700 --> 00:16:31,490 will feed on the white oaks 360 00:16:31,490 --> 00:16:33,823 and then preferentially feed on aspens. 361 00:16:35,320 --> 00:16:38,150 Then they'll move on to the red oaks 362 00:16:38,150 --> 00:16:41,340 and then the red maples 363 00:16:41,340 --> 00:16:44,800 and they'll feed on pretty much everything except ashwood, 364 00:16:44,800 --> 00:16:48,770 since we've lost most of the ash, to a pauper or sassafras, 365 00:16:48,770 --> 00:16:50,123 and a real surprise, 366 00:16:51,010 --> 00:16:53,300 I've seen areas where every tree is stripped 367 00:16:53,300 --> 00:16:55,893 except for sassafras and American chestnut. 368 00:16:57,400 --> 00:16:59,680 - [Jerry] Jeff, this is Jerry in New York. 369 00:16:59,680 --> 00:17:01,480 Great presentation, thanks for that. 370 00:17:02,330 --> 00:17:06,673 I'm wondering what you think the role is for, 371 00:17:07,609 --> 00:17:08,584 (laughs) 372 00:17:08,584 --> 00:17:10,910 what you think the role is for a time, 373 00:17:10,910 --> 00:17:12,270 obviously, you mentioned drought, 374 00:17:12,270 --> 00:17:16,230 but, you know, we in New York have had periods of drought 375 00:17:16,230 --> 00:17:18,540 and not had the same outbreak 376 00:17:18,540 --> 00:17:20,970 that you guys in Connecticut and Rhode Island had 377 00:17:20,970 --> 00:17:22,760 in the same types of stands. 378 00:17:22,760 --> 00:17:26,828 So is that a bigger role for maybe the national enemies, 379 00:17:26,828 --> 00:17:30,313 (indistinct) or what do you think? 380 00:17:32,240 --> 00:17:33,430 - I'll tell you, it's really interesting. 381 00:17:33,430 --> 00:17:36,310 If you really dive into the literature, 382 00:17:36,310 --> 00:17:38,870 it seems like drought during outbreak 383 00:17:38,870 --> 00:17:43,870 exasperates mortality, but drought per se 384 00:17:44,010 --> 00:17:48,530 doesn't set up a gypsy moth outbreak. 385 00:17:48,530 --> 00:17:52,113 But a drought allows, and (indistinct), the fungus, 386 00:17:53,570 --> 00:17:56,793 to, it's not so much drought as you really need to have, 387 00:17:57,790 --> 00:18:00,360 you know, multi-day periods during May. 388 00:18:00,360 --> 00:18:03,280 So fungus is pretty much always out there, 389 00:18:03,280 --> 00:18:04,910 but it'll hit the early instars 390 00:18:04,910 --> 00:18:08,460 and then it'll bioamplify in those early instars 391 00:18:08,460 --> 00:18:10,890 and then if you've got more repeated periods 392 00:18:10,890 --> 00:18:13,623 of high humidity and high moisture, 393 00:18:14,500 --> 00:18:17,610 the fungus will, I'm pregnant to say this 'cause I'm not 394 00:18:19,260 --> 00:18:22,090 a fungus guy, but it'll sporulate 395 00:18:22,090 --> 00:18:23,740 and it'll spread to the later instars 396 00:18:23,740 --> 00:18:26,570 and that's when you start seeing the massive die off 397 00:18:26,570 --> 00:18:28,070 and you start seeing the caterpillars 398 00:18:28,070 --> 00:18:29,330 falling out of the trees 399 00:18:29,330 --> 00:18:32,683 and the woods smell like rotten meat when it gets that bad. 400 00:18:33,930 --> 00:18:37,157 - [Judy] There is a comment in the chat box, too. 401 00:18:37,157 --> 00:18:37,990 - Yeah. 402 00:18:40,007 --> 00:18:42,687 "The timing of the leaf out, red oak, white oak." 403 00:18:43,650 --> 00:18:45,200 I was gonna say, well, at least down here, 404 00:18:45,200 --> 00:18:47,660 they tend to leaf out pretty close to each other 405 00:18:47,660 --> 00:18:48,870 within a couple of days. 406 00:18:48,870 --> 00:18:50,490 And I'll tell you, man, 407 00:18:50,490 --> 00:18:51,323 that could be, 408 00:18:51,323 --> 00:18:54,970 I just honestly don't know. 409 00:18:54,970 --> 00:18:57,010 The one scary thing that would happen when we had, 410 00:18:57,010 --> 00:18:58,430 you know, a couple of years of drought 411 00:18:58,430 --> 00:19:02,517 before we had this last outbreak of defoliators, 412 00:19:02,517 --> 00:19:05,530 and I shouldn't say the first year of defoliation, 413 00:19:05,530 --> 00:19:08,480 we also had, the same time, with gypsy moth, 414 00:19:08,480 --> 00:19:11,030 there was a co-outbreak of forest tent caterpillar. 415 00:19:13,050 --> 00:19:14,870 And they were both covering all of the tires 416 00:19:14,870 --> 00:19:16,680 while we were out in the woods. 417 00:19:16,680 --> 00:19:20,010 But when both arborists and foresters 418 00:19:20,010 --> 00:19:21,360 were trying to drop trees, 419 00:19:21,360 --> 00:19:23,870 when you drop, especially the white oaks, 420 00:19:23,870 --> 00:19:25,730 if you're a harvest tree, when it hit the ground, 421 00:19:25,730 --> 00:19:27,640 the entire tree would shatter. 422 00:19:27,640 --> 00:19:30,640 There's very little bucking was needed on the trees. 423 00:19:30,640 --> 00:19:32,130 Arborists were saying when they were up there 424 00:19:32,130 --> 00:19:36,430 bringing down trees that were dead around folks' houses, 425 00:19:36,430 --> 00:19:38,970 the branches would just sometimes just shatter 426 00:19:38,970 --> 00:19:41,850 before they'd even cut all the way through the limbs. 427 00:19:41,850 --> 00:19:45,510 So it became a bit of a riskier proposition 428 00:19:45,510 --> 00:19:48,160 to actually be working out in the woods at that time. 429 00:19:50,290 --> 00:19:52,760 - [Judy] Thank you, Jeff, for that presentation 430 00:19:52,760 --> 00:19:55,620 and for all the questions and the answers. 431 00:19:55,620 --> 00:19:57,673 We'll see people at the next talk. 432 00:19:59,100 --> 00:19:59,933 - Take care, everyone. 433 00:19:59,933 --> 00:20:00,766 Thanks for listening.