Pests

Forest pests (Nova Scotia)
This NSDNR site includes information sheets on specific pests, newsletters and Annual reports (2007 and 2011)

Hope for hemlocks: New tactics found to fight deadly pest
Ad Crable in the Bay Journal Nov 23, 2020, Updated Dec 18, 2020. “One of Appalachia’s most important tree species may yet be saved”

Caterpillar Clash: The Budworm Returns
Article by Dave Sherwood in Winter 2014 issue of Northern Woodlands

Nov 8, 2019:

White pine blister rust
ONTARIO GOVERNMENT. Also view: Here’s what you need to know about Ontario’s majestic white pine by Bill Steer in ElliotLakeToday, June 24, 2020

Healthy Forest Partnership – Budworm Research
“The Healthy Forest Partnership is a four-year research initiative that started in 2014. We are dedicated to keeping our forest green and healthy by protecting it from spruce budworm.” based in N.B. Map includes N.S.

Beech Bark Disease: Proceedings of the Beech Bark Disease Symposium
USDA. Saranac Lake, New York June 16 – 18, 2004. 153 page PDF

Invasive Alien Species in Nova Scotia
MTRI ( Mersey Tobeatic Research Institute) Identification & Information Guide. 2012 Terrestrial species listed are Norway Maple (Acer platanoides), Oriental Bittersweet (Celastrus orbiculatus), Beech Bark Disease (Cryptococcus fagisuga, Neonectria spp.), Glossy Buckthorn (Frangula alnus), White Nose Syndrome (Geomyces destructans), Dutch Elm Disease (Hylurgopinus, Ophiostoma spp., & Scotylus spp.), Common Reed (Phragmites australis ssp. australis), Scots Pine (Pinus sylvestris), Rugosa Rose (Rosa rugosa). Glossy Buckthorn is prob the biggest threat to forests: “Tolerant of acidic conditions, this species is well adapted to invade a wide variety of natural habitats in Nova Scotia and may represent the greatest threat to plant communities in the province.”

Hemlock Woolly Adelgid is now in SW Nova Scotia
Post on this website, Aug 6, 2017, citing CFIA Press Release The arrival of these “hemlock vampires” in Nova Scotia is not good news.

Hemlock Vampire Denial in Nova Scotia 31Oct2019
Post on NSFN oct 31, 2019. Recent lit cited.

Hemlock Woolly Adelgid Documentary
Posted YouTube Feb 29, 2016. Cayuga Lake Watershed Network logo is on the video, otherwise, authorship is not indicated.

HWA Phenology
On NY State Hemlock Initiative

Shifts in vegetation and avian community structure following the decline of a foundational forest species, the eastern hemlock
M. J., D. A. W. Miller, M. R. Marshall and G. E. Stauffer. 2018. The Condor 120(3): 489-506.”… Species richness of hemlock-associated birds declined by an average of ∼1 species per survey location. The Black-throated Green Warbler (Setophaga virens) was the most strongly affected, declining in occupancy by 30%. All other species groups responded positively, with the strongest responses by species associated with the shrub layer, forest edge, and mature deciduous habitat. The species composition in hemlock and hardwood stands became more similar over time as the unique species assemblages in hemlock stands gave way to the avian community of the surrounding hardwood landscape, highlighting a trend toward homogenization of the avian community.”

Aphid-munching beetle could help save hemlock forests
By Gabriel PopkinJan. 15, 2020 in www.sciencemag.org. “An introduced beetle that eats the eggs of the hemlock woolly adelgid is showing promise”

Ten Years of Change in Beech Stand in North Central Maine Long Affected with Beech Bark Disease
MSC Thesis by Amada Farrar, University of Maine, 20013. American Beech was once an important component of our mixed Acadian forest but was severely impacted by beech bark disease incited by a scale insect that came to North America via Halifax. This study showed that clearcutting greatly increases mortality of seedlings from and spouts on disease-resistant trees and “demonstrates the importance of protecting resistant trees with uncut “islands” to insure their survival. Also see NS Naturally: Healthy N.S. beech trees spell hope. Article by Jamie Simpson, 2014.

Beech leaf-mining weevil
Kathleen Ryan on /www.invasiveinsects.ca
“The beech leaf-mining weevil (Orchestes fagi), also known as the beech flea weevil, was first detected in Canada in 2012 in Halifax, Nova Scotia. There it was causing severe defoliation on American beech trees (Fagus grandifolia). Subsequent surveys detected the presence of the insect near Sydney, Nova Scotia as well. The weevil is native to Europe where it is common. Currently, this insect is only known to be established in Nova Scotia, where several counties are infested. Read more. View also: European insects ravaging Nova Scotia beech trees CTV Atlantic July 26, 2017.

Chemical ecology of the invasive beech leaf mining weevil (Orchestes fagi L.) in Nova Scotia, Canada
Pawlowski, S. P. (2014) Honours thesis, Acadia University

Impact of the Invasive Beech Leaf-Mining Weevil, Orchestes fagi, on American Beech in Nova Scotia, Canada
Jonathan D. Sweeney et al., 2020. Front. For. Glob. Change, 24 “The beech leaf-mining weevil, Orchestes fagi (L.), is native to Europe where it commonly attacks European beech. The weevil was discovered infesting American beech in Halifax and Cape Breton Island, Nova Scotia, Canada in 2012, but anecdotal reports of defoliated beech in the Halifax area as early as 2006 suggest it established 5–10 years prior to its discovery. Our objectives were to estimate the impact of O. fagi on American beech in forested sites and urban areas, as well as its economic impact on owners of residential properties with mature American beech. In 2014, we established fifteen plots in forested sites containing a total of 260 American beech at Sandy Lake, Oakfield, and Mount Uniacke (n = 5 plots per site), where weevil infestation levels were moderate, low, and nil, respectively. At the same time we recorded the degree of cankering by beech bark disease on the main stems of each tree. Plots were visited annually to record tree mortality (2014–2019) and percentage of leaves with larval mines or adult feeding (2016–2019). Between 2016 and 2019, the percentage of leaves mined by weevil larvae increased from 6 to 59% at Mount Uniacke and from 48 to 83% at Oakfield. During the same period, cumulative beech mortality increased from 35 to 48% at Mount Uniacke and from 10 to 70% at Oakfield. At Sandy Lake in 2016, 88% of the beech trees had died and there were too few living beech to collect a leaf sample in our plots so estimates of weevil damage (87% of leaves with mines) were obtained from life table plots in the same area. Tree mortality was associated with severity of cankering by beech bark disease only at Mount Uniacke, the site with the fewest years of defoliation by the leaf-mining weevil. We also surveyed residents of Halifax in 2016 and 2018 to determine the rate of beech mortality and costs of tree removal in urban residential areas in the same region (within 40 km) of the forest areas. Relative to the forested sites at Sandy lake and Oakfield, mortality rates were lower in urban areas (32% in 2016, 44% in 2018), even though signs of weevil defoliation had been apparent to residents as early as 2011–2012.”

Insect Focus Beech Leaf Mining Weevil (Orchestes fagi L.)
Jeff Ogden in DNR’s Insectary Notes Spring 2015 pp 2-3 Basic info on the life cycle, detection in NS

Acadia gets research funds for alternatives to pesticides
http://www.kingscountynews.ca/ . July 7, 2017 “The Acadia project is Pan-Atlantic in scope with the participation of a number of federal labs including Natural Resources Canada’s Atlantic Forestry Centre in Fredericton, NB and Corner Brook, NL, universities and private companies, including Forest Protection Ltd. (FPL) and Sylvar Technologies of New Brunswick….The plan is to lead in the commercialization of products including traps, lures and sprays that attract, repulse or confuse the mating behaviour of targeted insects.”

Brown spots a sign of changes to come in Halifax’s tree canopy
CBC Sep 4, 2017. “Tar spot, a fungal infection, not harmful to [Norway Maple] trees in short term, but help limit lifespan”.

Pests that could be heading our way

Destructive, invasive beetle heading for the Maritimes
Globalnews.ca July 5, 2017 “The Emerald Ash Borer was first introduced in Canada and the United States in 2002 and is now making its way to Nova Scotia.”

Fungus serves as federal sidekick in fight to save forests
National Observer Nov 29, 2017. About a bark test to detect Emerald Ash Borer presence well before visible symptoms appear, and about a fungus that could be used to control it.

Cool weather can amplify attacks of tree-killing bark beetle
Dartmouth College, May 31, 2018 “As a warming climate invites the destructive southern pine beetle to expand its northern range, the cooler weather in this new habitat can potentially increase the lethality of the insect’s assault on trees, according to a new study from Dartmouth College.” Also, on www.pressherald.com, Jun 9, 2018: Cooler climates can raise tree deaths from southern pine beetles. “The insect could reach Nova Scotia by 2020… fall and winter temperatures can heighten the intensity of attacks in the spring, but white pines like those in Maine are usually spared…The southern pine beetle’s primary targets are pitch pines, red pines and jack pines.”

OPINION: Alien invader threatening to devastate Sarnia’s oak trees
November 14, 2017 in the Sarnia Journal
“…It blocks the tree’s vascular system, preventing it from taking in food and water. Wilting starts at the top, works its way down, and within just weeks or months a large and otherwise healthy oak tree is dead. This devastating disease has been heading slowly northward through the eastern U.S. Though it hasn’t been confirmed in Canada yet it has reached St. Clair County in Michigan, just across the river, and Belle Island in the Detroit River….U.S. foresters say no species of oak is immune, but the family of trees known as red oaks is especially vulnerable to infection and death.”

University researchers develop tree disease detection device
Minnesota Daily, dec 7, 2017. “Researchers hope the device will make oak wilt detection cheaper and faster.”

To save iconic American chestnut, researchers plan introduction of genetically engineered tree into the wild
By Gabriel Popkin Science Magazine Aug 29, 2018. “…These American chestnut trees (Castanea dentata) are under such tight security because they are genetically modified organisms, engineered to resist a deadly blight that has all but erased the once widespread species from North American forests. Now, Newhouse and his colleagues hope to use the GM chestnuts to restore the tree to its former home. In the coming weeks, they plan to formally ask U.S. regulators for approval to breed their trees with nonengineered relatives and plant them in forests.”

Spruce Budworm

Spruce Budworm on cue
Post on this website, August 18, 2016. The anticipated outbreak of spruce budworm is pretty well on cue (30-40 years between outbreaks), so one might wonder why such planning has not been integral to forest management policies since the end of the last outbreak (1983).

Spray targets 80,000 hectares of N.B. forest as spruce budworm makes inroads
CBC July 21, 2017

Spruce Budworm: An Early Intervention Strategy
Natural Resources Canada video. Transcript also available. “Dr. Rob Johns: This is a new approach to managing spruce budworm outbreaks where we’re essentially controlling hot spots along the leading edge of the outbreak. We’re hoping this is going to slow or perhaps prevent the spread of the outbreak.”

Healthy Forest Partnership
“The Healthy Forest Partnership is a four-year research initiative that started in 2014. We are dedicated to keeping our forest green and healthy by protecting it from spruce budworm”

As Eastern hemlock trees die off, an art installation creates space for reflection and mourning
Savannah Christiansen on www.pri.org Oct 29, 2018

https://www.cbc.ca/news/canada/ottawa/beach-bark-disease-tree-death-1.4900548
Ontario’s beech trees are facing a slow demise. Here’s why
CBC News · Posted: Nov 12, 2018

Native forest plants rebound when invasive shrubs are removed
Jeff Mulhollem in Penn State news, may 14, 2019, citing this journal paper:

Erynn Maynard-Bean, Margot Kaye. Invasive shrub removal benefits native plants in an eastern deciduous forest of North America. Invasive Plant Science and Management, 2019; 12 (1): 3 DOI: 10.1017/inp.2018.35

Ontario Proposing Plan To Help Keep Province Free of Deadly Deer Disease
June 10, 2019 10:15 A.M.Ontario Ministry of Natural Resources and Forestry News Release. “The Government has developed a plan to allow the province to act quickly if Chronic Wasting Disease (CWD) – a progressive, fatal brain disease that mostly affects deer and elk – is discovered in Ontario.

The Troubles of “Invasive” Plants: Collateral Damage, Monsanto, and the Tragedy of Pinyon-Juniper eradication
by NICOLE PATRICE HILL – KOLLIBRI TERRE SONNENBLUME in CounterPunch Jan 4, 2019. “This is part one of a three part series. In this part we discuss: a) the negative effects of invasive plant removal methods, b) the involvement of Monsanto in popularizing invasion biology, and c) the tragedy of Pinyon-Juniper forest eradication in the western U.S. under the rubric of “native invasive species management.”…””The issue of invasives has been receiving increasing attention from the power structure since 1999. Why is that? Let’s assume the issues as stated are real and have worsened since then; even if that’s the case, it’s still doesn’t necessarily answer the question. The climate crisis has increased tremendously since 1999 but there has been no concomitant ramping up of resources to address it, and it’s a bigger one: literally existential for the human race. Other crises have also worsened—over drinking water, affordable housing, and access to healthy food, for example—and none have merited an executive-ordered brain trust. No, the rising level of attention for invasives in officialdom is not about science or ecology or need; it’s simply reflective of the growing opportunities for profit by certain powerful players, most prominently herbicide manufacturers.”

Millions of Beetles Are Wiping Out Forests All Across the World
By Jen Skeritt for Bloomberg News August 17, 2020 “The pest are eating away at trees as climate change warms winters. Infestations have the potential to worsen future emissions.”

Birds versus bees: Here are the winners and losers in the great pesticide trade-off
By Erik StokstadApr. 1, 2021 in sciencemag.org

Yellow Witches’ Broom
Page on DNR/L&F website
This rust fungus causes abnormal shoot growth on balsam fir. Usually not severe, but can be a serious problem in Christmas tree plantations especially when balsam fir is grown on heavy agricultural soils where chickweed is common. This rust fungus infects fir buds in the spring and invades the young shoots. The perennial brooms grow slowly the first year and cause only slight, elongated swellings that are very difficult to detect on infected shoots. The following spring, buds on the infected twigs produce upright shoots that are thicker and shorter than normal. Needles of the new shoots are stunted, thickened, pale green and arranged in a spiral curve. During the summer, the needles become yellow; in autumn they die and drop off, leaving the broom empty of foliage during the winter. The broom produces a new crop of pale green needles in spring which release spores to infect its alternate host, chickweed. When the rust matures on the chickweed, it releases spores to infect the trees. Damage Symptoms: Trees with visible brooms. Needles that are stunted, turn from green to pale green to yellow, then die and drop off. Branches affected by the brooms are deformed by galls and cankers.

The Northeast’s hemlock trees face extinction. A tiny fly could save them.
By Zoya Teirstein, Grist August 4, 2021