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Index of Subjects --Apple-Mail-165--672211141 Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset=US-ASCII; delsp=yes; format=flowed Hi folks, On 17-May-07, at 7:14 PM, David & Alison Webster wrote: > Dear All, May 17, 2007 > A recent article (Chron.Hrld.; May 16) on the Brown Spruce > Longhorn Beetle includes an explanation, attributed to Greg > Cunningham, that "The storm (Juan) created so much ground material > that it gave the beetle an ideal opportunity to multiply." > > So the admission has finally emerged indirectly that the BSLB > can not attack healthy trees. If it could do so then the Juan swath > of damaged trees would not have provided this "...ideal > opportunity...". > > It takes a while sometimes. A very perceptive observation, the significance of which still continues to evade the CFIA! :-> The CFIA have just released the results of their 2006 BSLB survey. Interested readers can see it here: http://www.inspection.gc.ca/english/plaveg/pestrava/tetfus/ bslb_update2006e.shtml They appear to have caught ~ 45 beetles (the number of positive traps or wood bolts). In the attached distribution map of sites, it appears that the distribution of the BSLB has increased, almost entirely in the zone of trees downed by Hurricane Juan. It has been some 3.5 years since the hurricane hit NS and in the wake of the very considerable quantities of dead and dying wood generated by this event, one would expect to see an increase in the saproxylic insect populations (those involved in the decay and decomposition of wood) in this area. After several years, when the dust settles on the post- Juan decomposition cycle, one will then expect to witness a corresponding decrease in saproxylic insect populations as their food supply dwindles. This cycle has, of course, various wrinkles, since it may take a few years for trees that were severely damaged by Juan to actually expire. Also saproxylic invertebrates colonize decaying would in a series of waves, there being at least three major stages in the decomposition of wood, each with its own suite of associated insects. In fact the BSLB, like all longhorn beetles are phloem/cambium feeders, and are thus in the first wave of this cycle. For them the food supply will run out first. As Dave points out, what's missing in the CFIA's analysis, is an appreciation of the fact that this pattern precisely illustrates what Friends of Point Pleasant Park and an increasing array of environmental groups have been pointing out, namely that the BSLB feeds on dead and dying trees (precisely as it does across Eurasia) and doesn't affect healthy forests. There is also a major omission in the information that CFIA consistently provides, namely what other saproxylic insects - and their numbers - are caught in the trapping effort for the BSLB. My own dataset from Point Pleasant Park during the 2000-2003 interval shows 21 species of longhorn beetles (Cerambycidae) present - one of which was the BSLB. Amongst these, BSLB's accounted for 21% of individuals. This is only "semi-quantitative" information since the dataset does not reflect a quantitative sampling program to measure the relative abundances of these species. Nonetheless it illustrates the fact that where BSLB are found in dead and dying trees, there are many other native species present in substantial quantities. If one includes the bark beetles (Scolytinae), and jewel beetles (Buprestidae) in the mix (two other prominent groups of cambium- feeding, saproxylic beetles), the BSLB is only one of 54 species present (all the others are native species in Nova Scotia), and the proportion of BSLB individuals drops to 2.7%. Why does this matter? Again, as Friends of Point Pleasant Park and an increasing array of environmental groups have been pointing out, there is simply no evidence that the BSLB is in any appreciable way, ecologically different from the many native species of saproxylic insects and invertebrates found in the province. They all feed on dead and dying wood and present no threat to healthy trees and forests. Seven years have passed since this issue came onto the public radar, and the CFIA has not even attempted to address the issue. Attempts to exterminate, "contain" or even "slow down" the BSLB are pointless if: a) there are a whole suite of native insects doing the exact same thing; and b) what they are doing is a natural, healthy, and important activity, namely expediting the natural processes of the decay and decomposition of wood. Without such saproxylic insects, our forests would be piled to the treeline with dead wood, and the recycling of carbon and nutrients in the forest ecosystem would long ago have ceased. Despite all of this, the CFIA has still not provided any evidence that their campaign - and all the associated expenses to taxpayers and inconveniences to property owners and wood-lot owners and operators - have any justification or any basis in fact. All the best, Christopher Majka Friends of Point Pleasant Park --Apple-Mail-165--672211141 Content-Transfer-Encoding: quoted-printable Content-Type: text/html; charset=ISO-8859-1 <HTML><BODY style=3D"word-wrap: break-word; -khtml-nbsp-mode: space; = -khtml-line-break: after-white-space; ">Hi folks,<DIV><BR><DIV><DIV>On = 17-May-07, at 7:14 PM, David & Alison Webster wrote:</DIV><BR = class=3D"Apple-interchange-newline"><BLOCKQUOTE type=3D"cite"><DIV = style=3D"margin-top: 0px; margin-right: 0px; margin-bottom: 0px; = margin-left: 0px; ">Dear All,<SPAN class=3D"Apple-converted-space">=A0 =A0= =A0 =A0 =A0 =A0 </SPAN>May 17, 2007</DIV><DIV style=3D"margin-top: 0px; = margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><SPAN = class=3D"Apple-converted-space">=A0 =A0 </SPAN>A recent article = (Chron.Hrld.; May 16) on the Brown Spruce Longhorn Beetle includes an = explanation, attributed to Greg Cunningham, that<SPAN = class=3D"Apple-converted-space">=A0 </SPAN>"The storm (Juan) created so = much ground material that it gave the beetle an ideal opportunity to = multiply."</DIV><DIV style=3D"margin-top: 0px; margin-right: 0px; = margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><BR></DIV><DIV = style=3D"margin-top: 0px; margin-right: 0px; margin-bottom: 0px; = margin-left: 0px; "><SPAN class=3D"Apple-converted-space">=A0=A0 = </SPAN>So the admission has finally emerged indirectly that the BSLB can = not attack healthy trees. If it could do so then the Juan swath of = damaged trees would not have provided this "...ideal = opportunity...".</DIV><DIV style=3D"margin-top: 0px; margin-right: 0px; = margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><BR></DIV><DIV = style=3D"margin-top: 0px; margin-right: 0px; margin-bottom: 0px; = margin-left: 0px; "><SPAN class=3D"Apple-converted-space">=A0=A0 = </SPAN>It takes a while sometimes.</DIV></BLOCKQUOTE></DIV><DIV><BR = class=3D"khtml-block-placeholder"></DIV>A very perceptive observation, = the significance of which still continues to evade the CFIA! = :-></DIV><DIV><BR class=3D"khtml-block-placeholder"></DIV><DIV>The = CFIA have just released the results of their 2006 BSLB survey. = Interested readers can see it here:</DIV><DIV><A = href=3D"http://www.inspection.gc.ca/english/plaveg/pestrava/tetfus/bslb_up= date2006e.shtml">http://www.inspection.gc.ca/english/plaveg/pestrava/tetfu= s/bslb_update2006e.shtml</A></DIV><DIV><BR = class=3D"khtml-block-placeholder"></DIV><DIV>They appear to have caught = ~ 45 beetles (the number of positive traps or wood bolts). In the = attached distribution map of sites, it appears that the distribution of = the BSLB has increased, almost=A0entirely in the zone of trees downed by = Hurricane Juan. It has been some 3.5 years since the hurricane hit NS = and in the wake of the very considerable quantities of dead and dying = wood generated by this event, one would expect to see an <I>increase</I> = in the saproxylic insect populations (those involved in the decay and = decomposition of wood) in this area. After several years, when the dust = settles on the post-Juan decomposition cycle, one will then expect to = witness a corresponding <I>decrease</I> in=A0saproxylic insect = populations as their food supply dwindles.=A0</DIV><DIV><BR = class=3D"khtml-block-placeholder"></DIV><DIV><SPAN = class=3D"Apple-style-span">This cycle has, of course, various wrinkles, = since it may take a few years for trees that were severely damaged by = Juan to actually expire. Also saproxylic invertebrates colonize decaying = would in a series of waves, there being at least three major stages in = the decomposition of wood, each with its own suite of associated = insects. In fact the BSLB, like all longhorn beetles are phloem/cambium = feeders, and are thus in the first wave of this cycle. For them the food = supply will run out first.</SPAN></DIV><DIV><BR = class=3D"khtml-block-placeholder"></DIV><DIV><SPAN = class=3D"Apple-style-span">As Dave points out, what's missing in the = CFIA's analysis, is an appreciation of the fact that this pattern = precisely illustrates what Friends of Point Pleasant Park and an = increasing array of environmental groups have been pointing out, namely = that the BSLB feeds on dead and dying trees (precisely as it does across = Eurasia) and doesn't affect healthy forests.=A0There is also a major = omission in the information that CFIA consistently provides, namely what = other saproxylic insects - and their numbers - are caught in the = trapping effort for the BSLB.</SPAN></DIV><DIV><BR = class=3D"khtml-block-placeholder"></DIV><DIV><SPAN = class=3D"Apple-style-span">My own dataset from Point Pleasant Park = during the 2000-2003 interval shows 21 species of longhorn beetles = (Cerambycidae) present - one of which was the BSLB. Amongst = these,=A0BSLB's=A0accounted for 21% of individuals. This is only = "semi-quantitative" information since the dataset does not reflect = a=A0quantitative sampling program to measure the relative abundances of = these species.=A0Nonetheless it=A0illustrates the fact that where BSLB = are found in dead and dying trees, there are many other <I>native</I> = species present in substantial quantities. If one includes the bark = beetles (Scolytinae), and jewel beetles (Buprestidae) in the mix (two = other prominent groups of cambium-feeding, saproxylic beetles), the BSLB = is only one of 54 species present (all the others are native species in = Nova Scotia), and the proportion of BSLB individuals drops to = 2.7%.</SPAN></DIV><DIV><BR = class=3D"khtml-block-placeholder"></DIV><DIV>Why does this = matter?</DIV><DIV><BR class=3D"khtml-block-placeholder"></DIV><DIV>Again, = as=A0Friends of Point Pleasant Park and an increasing array of = environmental groups have been pointing out, there is simply no evidence = that the BSLB is in any appreciable way, ecologically different from the = many native species of saproxylic insects and invertebrates found in the = province. They all feed on dead and dying wood and present no threat to = healthy trees and forests. Seven years have passed since this issue came = onto the public radar, and the CFIA has not even attempted to address = the issue. Attempts to exterminate, "contain" or even "slow down" the = BSLB are pointless if:</DIV><DIV><BR = class=3D"khtml-block-placeholder"></DIV><DIV>a) there are a whole suite = of native insects doing the exact same thing; and=A0</DIV><DIV>b) what = they are doing is a natural, healthy, and important activity, namely = expediting the natural processes of the decay and decomposition of = wood.=A0</DIV><DIV><BR = class=3D"khtml-block-placeholder"></DIV><DIV>Without such saproxylic = insects, our forests would be piled to the treeline with dead wood, and = the=A0recycling of carbon and nutrients in the forest ecosystem would = long ago have ceased.</DIV><DIV><BR = class=3D"khtml-block-placeholder"></DIV><DIV>Despite all of this, the = CFIA has still not provided any evidence that their campaign - and all = the associated expenses to taxpayers and inconveniences to property = owners and=A0wood-lot owners and operators - have any justification or = any basis in fact.=A0</DIV><DIV><BR = class=3D"khtml-block-placeholder"></DIV><DIV>All the best,</DIV><DIV><BR = class=3D"khtml-block-placeholder"></DIV><DIV>Christopher = Majka</DIV><DIV>Friends of Point Pleasant = Park</DIV><DIV><BR></DIV></BODY></HTML>= --Apple-Mail-165--672211141--
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