It was the summer of 2017, did you see it?
The Populus tremuloides (Trembling Aspen or Quaking Aspen) groves were struggling, and suffering tremendously. The defoliation caused by the Tent Caterpillar Malacosoma disstria was so severe, that combined with the severe drought, the vigour and vitality of the Aspen Trees was greatly reduced. 2017 saw the fourth year of the Tent Caterpillar infestation in Saskatoon. When healthy trees that are completely stripped of their leaves are able to refoliate their leaves after the caterpillars have feasted, however the second growth is smaller and, indeed, may be inadequate to compensate for the damage caused. The attack of the caterpillars may even kill the top of the tree, side branches and even the whole tree may expire with multi-years of excessive defoliation.
James J. Worrall et al, explains that drought, tent caterpillars and other factors contribute to the decline of Trembling Aspens. Severe drought precipitates the most drastic decline, followed by foliage stripped by tent caterpillars year after year. Aspen stands cannot recover from such shocks to the system on a multiyear basis, without relief.
“It’s almost as if nature has forgotten how to rain in parts of Saskatchewan,” said David Phillips, senior Climatologist with Environment Canada, who goes on to explain that, “It really does show you the kind of climate you have: a desert — dry, semi-arid, almost like Pheonix, Ariz. — where the days can be very hot, and in this case bone dry and not a cloud in the sky. All that heat from the day radiates into space … It left the nights relatively cool.” Saskatoon received only 243.6 millimetres [9.6 inches] of precipitation, bringing 2017 into the top five driest years for the city.
Not only was 2017 setting records for the driest years in history books, the problem for the Trembling Aspen was compounded as being the worst for the Tent Caterpillar plague. “We’re in a boom period for the tent caterpillar,”  ” said Tyler Wist, Field crop entomologist for Agriculture and AgriFood Canada. The tent caterpillar has a natural predator in birds, as well as the eggs of the sarcophagid fly.
Effects on overall health of aspen. Repeated defoliation by forest tent caterpillar may not allow trees to recover to a normal state of health, which can lead to decline. ~ Natural Resources Canada“
Following two or more years of severe feeding there is a general decline in tree health, including twig and branch dieback. After three or four consecutive years of being stripped of their leaves trees can be weakened and may be more susceptible to insects, such as wood borers, and stem disease. Following forest tent caterpillar infestations the incidence of hypoxylon canker, a fungal stem disease, may increase and cause extensive damage in aspen forests. “~ Forestry Branch
Late spring frosts kill buds leading to early, mass larval stravation. Alberta Government.“When populations are low, the egg masses on small plants can be removed by hand and destroyed between July and the following spring. Hand picking can inflict significant larval mortality.Destruction of occupied tents by hand or with a brush leads to colony collapse. Pruning to remove egg masses, tents, or groups of larvae must be done sparingly to avoid injuring the plant. Using fire to accomplish this is not recommended as it damages the plant more than the defoliation.”~Forest Health Protection
“Jack Schultz, a Pennsylvania State University entomologist… discovered that aspens react chemically to insect attack. Soon after the caterpillar start chewing, the trees’ remaining leaves produce bitter-tasting phenol compounds to discourage further eating” 
1. Allen Bonnie.
‘The damage is done’: Home electricity boxes igniting in Sask. drought
Regina’s driest July in 130 years also threatening livestock, crops and farmers’ livelihoods” CBC News Aug 04, 2017
2 Climenhaga, Christy. Regina experiences driest July in 130 years. July topped the charts for hot and dry weather in southern Saskatchewan CBC News Aug 01, 2017
3. Climenhaga, Christy. 2017 driest year on record for some Sask. communities
Driest year ever for Assiniboia, Moose Jaw; Regina saw 2nd-driest year, with only 40% of normal precipitation CBC News. January 6, 2018.
4. Climenhaga, Christy. Regina and Swift Current could see their driest July on record
Southern Saskatchewan still waiting for rain after bone-dry July CBC News July 27, 2017.
5. Fergus, Charles. Trees of Pennsylvania and the Northeast. Edition illustrated Publisher Stackpole Books, 2002 ISBN 0811720926, 9780811720922
5. Giles, David. Forest tent caterpillars invade Saskatoon Global News. May 24, 2017
6. Graham, Jennifer. Dry weather withering crops, stressing farmers in southern Saskatchewan The Canadian Press August 6, 2017
7. Graham, Jennifer. This Saskatchewan farm’s ground is so dry a wrench ‘would disappear’ in its cracks Environment Canada figures show Regina had only 1.8 millimetres of rain last month — the driest July in 130 years. The Canadian Press. August 6, 2017
8. Its more than rare.” Environment Canada says southern Saskatchewan’s dry July will break records 620 CKRM Juy 27, 2017.
9. Knox, Shawn. Dundurn, Sask. woman tired of tent caterpillar infestation Global News. June 1, 2017.
10. Lizee, Tiffany. Southern Saskatchewan in drought for almost a year Global News. October 14, 2017
11. Martell, Creeden. ‘They just keep coming’: Tent caterpillar invasion coats Sask. home in insects — and feces Saskatchewan in a boom period for tent caterpillars CBC News May 31, 2017
12. Petrow, Erin. Caterpillars thrive for the fourth consecutive year Saskatoon Star Phoenix. May 24, 2017.
13. Prestwich, Emma Caterpillars Cover Saskatchewan Woman’s Property And It’s Super Disgusting Huffpost Canada.
14. Squires, Malcolm F. Dynamic Forest: Man Versus Nature in the Boreal Forest
Volume 7 of Point of View Contributor John Kennedy Naysmith
Edition illustrated Publisher Dundurn, 2017 ISBN 1459739345, 9781459739345
16. Tu, Chau Earth’s biggest living thing might be a tree with thousands of clones Science Friday. May 5, 2015
17. Worrall, James J., Gerald E. Rehfeldt, Andreas Hamann, Edward H. Hogg, Suzanne B. Marchetti, Michael Michealian, and Laura K. Gray. Recent declines of Populus tremuloides in North America linked to climate Volume 299, Issue , July 2013, Pages 35-51
For more information:
Richard St. Barbe Baker Afforestation Area is located in Saskatoon, Saskatchewan, Canada north of Cedar Villa Road, within city limits, in the furthest south west area of the city. 52° 06′ 106° 45′
Part SE 23-36-6 – Afforestation Area – 241 Township Road 362-A
Part SE 23-36-6 – SW Off-Leash Recreation Area (Richard St. Barbe Baker Afforestation Area ) – 355 Township Road 362-A
S ½ 22-36-6 Richard St. Barbe Baker Afforestation Area (West of SW OLRA) – 467 Township Road 362-A
NE 21-36-6 “George Genereux” Afforestation Area – 133 Range Road 3063
Wikimapia Map: type in Richard St. Barbe Baker Afforestation Area
Google Maps South West Off Leash area location pin at parking lot
Web page: https://stbarbebaker.wordpress.com
Where is the Richard St. Barbe Baker Afforestation Area? with map
Facebook group page : Users of the St Barbe Baker Afforestation Area
Facebook: South West OLRA
Contact the Meewasin Valley Authority in Saskatoon, Saskatchewan, Canada. The MVA has begun a Richard St. Barbe Baker Afforestation Area trust fund. If you wish to support the afforestation area with your donation, write a cheque to the “Meewasin Valley Authority Richard St. Barbe Baker Afforestation Area trust fund (MVA RSBBAA trust fund)”. Please and thank you!
Please contemplate joining the SOS Elms coalition or make a donation to SOS Elms ~ leave a message to support the afforestation area 😉