Category Archives: Insect Pests

Cornell Berry Diagnostics

The Cornell Cooperative Extensions Berry Diagnostic Tool is an excellent resource for anyone growing or interested in strawberries, raspberries, blueberries, blackberries, currants, and gooseberries. This online tool allows anyone to select a berry crop and then from a variety of descriptions of plant growth issues, deformities, discolorations, damage, or other indicator that occurs on the whole plant, flower, fruit, or vegetative to continue to diagnose the issue. Lots of photographs and links to in depth articles are included about many diagnoses to really get to the “root” of the issue. Finally, recommendations for management of the issue can be selected after referring to the images and descriptions
Citation: Cornell Cooperative Extension. 2016. Cornell Fruit Berry Diagnostic Tool. Available online: Diagnosis. Accessed: 12 October 201
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Spotted Wing Drosoplila

The Cornell University College of Agriculture and Life Sciences publishes a scientific newsletter called the New York Berry News. These newsletters publish a variety of articles relating to berries and berry production including topics like: frost protection, post-harvest care, organic farming, pests and diseases, etc. I found the newsletter of great interest because of the wide diversity of topics all related to berries and creating healthy berry habitats whether wild or cultivated. Although most of these articles are mostly concentrated on berries growing in the New York State area, I found that much of the information given can be used as helpful tips and guides for growing and managing berries here in Alaska. One of the articles I found interesting is about the Spotted Wing Drosophila (SWD).

The Spotted Wing Drosophila (SWD) is an invasive small fruit fly that is a major pest problem for raspberries, blackberries and other cane berries as well as blueberries, strawberries, grapes and other small fruits and berries. The SWD is originally native to Asia but in 2008 the first confirmation of SWD was found in California (Wold-Burkness & Hahn) and since then has spread throughout most of the fruit growing regions in the United States. Found in New York State in 2012, the SWD has caused serious crop losses in every year since (Wallingford & Loeb).

The SWD is a small fly that typically measures only about 2-3mm long, has big red eyes and a yellow/brown body (Wold-Burkness & Hahn). The abdomen has small rings around it and large clear wings. They are hard to identify against other small fruit flies, but the males do have a large black spot near the top and back half of their clear wings (Wold-Burkness & Hahn). The SWD larvae are commonly called maggots and have small tubular shaped bodies with no legs.

The adult SWD inserts its eggs under the skin of young fruit both wild and cultivated. In New York the SWD populations are relatively low during the spring months, but as fruit begins to ripen and berries are in large abundance the populations are also in large concentrations and this is why so many berry crops are suffering (Wallingford & Loeb). The adult SWD flies feed on thin skinned soft fruit such as berries, grapes, and plums. The larvae will feed on the fruit under the skin and cause the fruit tissue to be browned and squishy. Sometimes the damage to the fruit that the larvae produce will go unnoticed until after harvest and can be seriously detrimental to harvest production.

In New York pesticides are used in effort to control SWD populations but often weekly doses are needed to keep infestation levels down (Wallingford & Loeb). Weekly insecticide applications can be expensive and also damaging to the plants health and production rates and many growers are experiencing “sprayers fatigue” (Walligford & Loeb). In addition to the damage the flies cause and the damage from over spraying of pesticides, these flies can make the plants more susceptible to infestation by other insects, rot fungi and diseases (Wold-Burkness & Hahn).

There are currently many studies on the SWD and their effects on fruit production including studies relating to growth cycles, winter/cold survival, organic pest control, cultivating techniques, etc. These are relatively new pests in the United States and although I cannot find anything confirming their existence in Alaska, it seems that it is only a matter of time before we are also actively battling the Spotted Wind Drosophila. If you are looking for more information about the SWD I have attached both the New York Berry News article as well as a study conducted by the University of Minnesota Cooperative Extension Program. LH Fairbanks

Wallingfor, A. and Loeb, G. 2016. Spotted Wing Drosophila: Winter Biology. New York Berry News. 15 (2): 5-18. Available online: http://www.fruit.cornell.edu/nybn/newslettpdfs/2016/nybn1502.pdf Accessed: 10 Oct. 2016.

Wold-Burkness, S. and Hahn, J. 2016. Spotted Wing Drosophila in Home Gardens. Insects. University of Minnesota, Extension. Available online: http://www.extension.umn.edu/garden/insects/find/spotted-wing-drosophila-in-home-gardens/ Accessed: 10 Oct. 2016.

 

Spruce Bark Beetles and Berries

Being from the Kenai Peninsula and having first hand experience with spruce bark beetle die off in my home town of Moose Pass, it was interesting to read the effects the spruce bark beetle die off had on berry populations in the area. This article goes into depth about the effect tree coverage had on the berry stands in the area after the trees began to grow back after the spruce bark beetle die off. Each berry tested had slightly different results, but for the most part they averaged being the most productive at 50% coverage, then loosing productivity after that. BE Moose Pass, AK

Abstract: “Land managers on the Kenai Peninsula have responded to recent extensive infestations of forests by spruce beetles (Dendroctonus rufipennis (Kirby)) and associated increased fire risk with a variety of management approaches. To provide additional ecological information upon which to base these management prescriptions, we evaluated the response of the cover of berry species to variations in landscape factors and environmental conditions, including crown closure. Data were sufficient to describe the response of cover of bunchberry dogwood (Cornus canadensis), black crowberry (Empetrum nigrum), false toadflax (Geocaulon lividum), strawberryleaf raspberry (Rubus pedatus), lingonberry (Vaccinium vitis-idaea), and a combination of 24 other species through multinomial logistic regression. Crown closure and forest overstory type significantly influenced the cover of all berry species. Increasing crown closure had a negative effect on all berry species except strawberryleaf raspberry. Level of infestation by spruce beetles was significantly related to the cover of all species except lingonberry. Our findings indicate that spruce forests may be managed to enhance berry cover and that choice of management technique (e.g., timber harvest, prescribed fire) will likely result in different outcomes.”

During, L.H., M.I. Goldstein, S.M. Howell and C.S. Nations. 2008. Response of the cover of berry-producing species to ecological factors on the Kenai Peninsula, Alaska, USA Canadian Journal of Forest Research.Vol. 38, No. 5 : pp. 1244-1259

Honeyberry, haskap pests

During this week’s lecture we learned about the Honeyberry aka Haskap aka Sweetberry Honeysuckle aka a plethora of other names. Two pests of this plant were mentioned but some important ones I’ve personally encountered the past two years were not. These pests are robins (Turdus migratorius) and leaf rollers (Archips rosana).

I find the Latin species name for the robin very appropriate, Turdus. Once the robins have located your Honeyberry patch, they will visit every day until the berries are close to ripening and will devour them before you get a chance to even taste them for readiness. The devious little creatures will visit your patch every year once they know you have them. The best way to battle these pests is to build a net cage around the patch. Just laying netting on top and around does not prevent thievery. Robins will sit on top of the net and slip under the net. The net must be several feet away from the berries and securely attached to the ground to prevent any sneaking below the net. I constructed a cage around my small patch using the smallest size of bird netting available and some old fence posts. Ground staples are excellent for securing the netting to the ground. I was able to harvest nine pounds of berries this year compared to the previous year of nothing! Next year, I intend to make a sturdier structure using ¾ inch PVC pipe, zip ties and bird netting. This will make for easier harvesting and look a little better.

The second pest I’ve dealt with is a leaf roller which for the last two years have attacked the growing tips of my honeyberries. The first year I encountered them I was not able to get a positive identification. This year, I captured a few samples and brought them to our local Cooperative Extension Service Office. The Integrated Pest Management (IPM) technician identified them initially as the Spear-Marked Black Moth (Rheumaptera hastate), however, a later identification was made as the Rose Tortrix Moth, (Archips rosana). The recommended control method was the use Bacillus thuringiensis (Bt) which I used but did not find very effective. I resorted to the best known method for insect pest control which is both effective and satisfying – pick and squish. I pruned my bushes this fall and removed all the leaves under the shrubs which could harbor overwintering pupae. Hopefully this next summer, I will see diminished problems with both the mentioned “pests”.

Gall roses

Below is a link to an entry about gall roses.  I couldn’t post photos here. 

Can you get hips from gall roses?

Insect identification resources

Being able to identify common insects in your berry stand will help you understand the relationships between plants and insects to help you become a better manager. A majority of the insects encountered in wild and cultivated berry stands play a beneficial role, such as pollinators or predators of potential pests, but some may be pests that decrease yields. Below are some resources that growers can consult as a starting point to learning more about insects in Alaska.

Books:

Insects of South-central Alaska by Dominique Collet. Although the title professes a focus on south-central Alaska, most species described can be found throughout the state. Excellent photos and descriptions make this a useful guide for the amateur through professional.

Agencies:

Cooperative Extension Service – Integrated Pest Management program. Have you collected an insect that you suspect is a pest? You can contact your local IPM technician for assistance identifying the insect and to provide you with management information. If you live in an area without a local Cooperative Extension Office and are good with a camera you can submit photos and information through the digital portal and be connected with the nearest IPM technician. Through the Extension IPM website you can also search available publications, such as Beneficial Insects and Spiders of Alaska.

US Forest Service – Forest Health Protection Program. Their website has resources about forest pests, some of which cross-over to berry plants.

Websites:

UAF Museum of the North – Entomology Collection. Learn more about the variety of insects that have been documented in Alaska. This website, and the searchable ARCTOS database, is most useful if you already know a bit about the insect in question and you are just checking to confirm its existence in Alaska. You can also look through all the insect records in ARCTOS that have pictures in the record.

Alaska Entomological Society – Are you REALLY interested in Alaska’s insects? You may want to consider joining this society to support further investigation and awareness of Alaska’s insects.

Berries Northwest – Although not Alaska specific, this site could be an excellent first step to diagnosing an insect or pest problem. You can search by crop or pest, then look through descriptions and management options.