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margin-bottom:.0001pt --000000000000ec01f7056f2857c8 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Hey Lance, It is also very like Pickett's findings in the 20s and 30s of the lack of effectiveness overtime of insecticide sprays in the Annapolis Valley apple orchards which led to development of Integrated Pest Management. Nick On Thu, Jun 21, 2018 at 11:43 AM, Laviolette, Lance < lance.laviolette@lmco.com> wrote: > Thanks Andrew. That makes sense given what is currently taking place with > anti-biotic resistant =E2=80=98germs=E2=80=99 in hospitals these days. > > > > Cheers, > > > > Lance > > > > > > *From:* naturens-owner@chebucto.ns.ca [mailto:naturens-owner@ > chebucto.ns.ca] *On Behalf Of *Hebda, Andrew J > *Sent:* Wednesday, June 20, 2018 9:01 PM > *To:* naturens@chebucto.ns.ca > *Subject:* EXTERNAL: RE: [NatureNS] Nova Scotian forest composition > > > > There was a publication from either the late 1950s or early 1960s by Dr R > E Balch called the Ecological Viewpoint... It came from either an episod= e > or a series from CBC University of the Air in which he discussed the > impact of contemporary and historical use of forest insecticides alterin= g > the dynamics of the budworm populations through selecting for resistant > forms. > > As I recall he noted that the cycling of those populations was regular an= d > predictable with relatively clearly defined maxima and minima in populati= on > sizes He noted that the selective pressure of the chemicals reduced the > cyclic nature of the species and resulted in an incremental increase in t= he > "low levels" of the species, to the point where the base level of those > populations was higher than the upper level o the normal population > oscillations. > > > > The point being that climate change is not necessarily the principal > driving force for specific species impacts. I will see if I can track do= wn > the publication (I think he may have been UNB Fredericton) > > > > A > > > ------------------------------ > > *From:* naturens-owner@chebucto.ns.ca [naturens-owner@chebucto.ns.ca] on > behalf of Laviolette, Lance [lance.laviolette@lmco.com] > *Sent:* June-20-18 5:19 PM > *To:* naturens@chebucto.ns.ca > *Subject:* Re: [NatureNS] Nova Scotian forest composition > > Hi Donna, > > > > Budworm is a native insect however it, like non-native insects, will > change the composition of Nova Scotia forests and that was what my origin= al > question was all about. As David has now pointed out, climate change will > also be a major =E2=80=98player=E2=80=99 in what the resulting forest wil= l look like in 20 > years. > > > > Predictions of what things will be in the future are simply an exercise i= n > assumptions so will not be interesting to everyone. Sticking with facts > then, the budworm=E2=80=99s cyclical impact on Maritime forests is as imp= ortant as > a non-native insect=E2=80=99s effect is. The impact on bird populations i= s a > well-studied phenomena. You mention that you are seeing a few more > Bay-breasted Warblers in the forest monitoring plots. I can tell you that > monitoring on Brier Island has shown that the population of both > Bay-breasted and Cape May Warblers have been rising dramatically over the > last 4-5 years. I expect they will continue to increase, as they did 40 > years ago as long as the Spruce Budworm populations remain high in the > Maritimes and the Gasp=C3=A9. The odd thing is that so far the expected r= ise in > Tennessee Warbler numbers hasn=E2=80=99t materialized in our observations= . Let us > know when you start detecting more of that species on your plots and I=E2= =80=99ll > do the same when numbers increase during migration on Brier Island. > > > > All the best, > > > > Lance > > > > Lance Laviolette > > Glen Robertson, Ontario > > > > > > > > *From:* naturens-owner@chebucto.ns.ca [mailto:naturens-owner@ > chebucto.ns.ca <naturens-owner@chebucto.ns.ca>] *On Behalf Of *Donna > Crossland > *Sent:* Tuesday, June 19, 2018 6:21 PM > *To:* naturens@chebucto.ns.ca > *Subject:* EXTERNAL: Re: [NatureNS] Nova Scotian forest composition > > > > It's best to avoid the 'company line' about "spruce budworm left > unchecked". This is a topic that the forest industry uses to instill pan= ic > to justify full scale harvesting of spruce and fir, complete with a spray > program, etc. Budworm is a native pest and should not enter the > conversations over exotics. It comes 'round every few decades, as we > know. Bay-breasted, Tennessee and other warbler species can increase > rapidly. We can sit back and enjoy watching natures responses to it. Thi= s > year I observed a few more Bay-breasted warblers in forest monitoring plo= ts > than previous years, and am questioning if they are from an increased > number resulting from the Qc population that decided to settle in southwe= st > NS this year instead of heading farther north after returning from the > tropics. > > The forest industry and DNR would have us "tinker" with this this natural > disturbance agent. But balsam fir was never "built to last". Titus Smit= h > referred to it as a nursery tree to shelter the growth of other late > successional tree species. Early entry harvesting in the pure fir/spruce > stands would mitigate the fear of trees dying all at once and wood going = to > 'waste' (industry thinking, not mine), but in actuality industry doesn't > want to float in the big machines for multiple, early, preemptive partia= l > harvests. The cheapest approach is to harvest all at once, so they wait > until the budworm hits (it was all so predictable), and then cries wolf > and harvests all at once. But this is the worst scenario for all other > ecosystem components including soil nutrients then exposed to leaching. > The budworm issue really hits a nerve. > > Balsam fir and spruce will regenerate after budworm. No worries there. > But hemlock will be repeatedly hit by HWA and not successfully > reestablish. It will be no more. That's the huge difference between > native pests and exotics. The latter situation leaves a permanent void. > Forests without hemlock, ash, and beech are likely imminent, perhaps in a= s > little as two decades, but who knows. Nature will figure something out, > but all these rapid changes are occurring because of human activities. > > > --=20 Dr. N.M.Hill Fern Hill Institute of Plant Conservation 424 Bentley Road, Berwick, NS, B0P 1E0 phone 902-698-0416 --000000000000ec01f7056f2857c8 Content-Type: text/html; charset="UTF-8"