Skip to main content

Derek Zerkowski

Highlights of crop scouting with WNYCMA

Round-up Ready volunteer corn weeds in Roundup Ready soybeans

This blog reflects upon what I’ve learned and enjoyed doing and seeing this summer at WNYCMA. It has been a good experience and I’ve taken a lot from it. I had the opportunity to see how to apply many of the principles and concept from the last several years of school to crop production. I really liked the weeks when there was a variety of crops and types of scouting to do. The opportunity to see how many of the crops are managed and how the pests are controlled was a great experience. I was told that this summer was more intense than a usual scouting season. The armyworms and drought conditions made us return to many of the fields to look for reoccurring pests or ones that could increase in population (i.e. spider mites) due to specific environmental conditions. Some of the farmers I scout for really got hit hard by armyworms, especially my farmers who had strip cropped grass hay fields next to their corn. Often I would scout for armyworms one week and find a low population and return the next week to find the populations increased in the hay fields and the “troop” of armyworms moved into the corn to eat that.

I also really liked the weed management aspect of crop scouting this summer. Call it weird, but I enjoyed identifying all the various weeds and how they grow and interfere with the growth of the crop in various ways. I got interested in weeds during the Weed Biology and Management class offered at Cornell and I look forward to taking the Weed Ecology and Management course with Toni next year, during my last undergrad semester. So for me, identifying and learning about the weeds was the most interesting of the job. I was given a “Weeds of the Northeast” book as I did my scouting and if I had any questions as to what I was looking at I would consult and review the book to verify the weed. Weeds were more an issue for the first half of the summer and after the crops got bigger and closed the canopy only a few weeds were commonly seen. These were usually common ones such as velvetleaf, pigweed, various annual grasses, and lambsquarters. We were always on the lookout for weed escapes and tried to rely on the residual action of the herbicides for control. The most commonly seen weed escape I saw this summer was Lambsquarters in soybeans. In a couple fields we had a few areas (of about 3 acres total in a 55 acre field) where there was lambsquarters t about the same height of the beans (about 32”). We talked to the farmer about the situation and after talking it over figured we would destroy more soybeans getting a sprayer out there to control the weeds. I think that my favorite crop to scout this summer was soybeans.

An early 1960’s John Deere 5010

I also have a passion for ag. equipment both new and old, but primarily the old stuff. I used to be a technician at a couple auto/truck and farm equipment repair shops before I decided to return to college. I have a few old John Deere and International Harvester tractors that I enjoy repairing. I enjoy getting these old tractors running and using for some field work. This summer’s experience allowed me to see all sorts of pieces of agricultural equipment from years gone by. While taking pictures of crops and crop pests I also took pictures of cool old pieces of equipment. The various agronomy skills I attained this summer at WNYCMA, interactions with the farmers, and the interesting places and things I saw made this a very worthwhile and memorable summer.

An old allis chalmers pull type combine

Wrapping up with WNYCMA

This is the start of my last week with WNYCMA. Monday will be my last trip down to Pennsylvania to scout for armyworms, leafhoppers, and corn rootworm beetles. The last few weeks have been very similar work as my previous blog post. I have a weekly rotation of crop scouting that consists of hitting certain farms each weekday and looking for increasing populations of different pests. Early in the week, I head south and work in Pennsylvania and scout from 3 to 4 farms down there. Some farms are on the “full service” plan and we scout these farms more frequently and intensely than the farms who don’t opt for the full service plan. In PA, I have a few dairy farms and a hog farm to scout.
Later in the week I work in farms around the Belmont and Wellsville area. I have a couple mixed crop and livestock farms in this area. The corn for grain that I scout in the Genesee Valley area is on well drained gravel ground and as a result of the midsummer drought is very short and stunted and has already tasseled. Much of this corn is 3 to 4 feet tall and the leaves have desiccated up to the ear leaf. The dry weather has also brought issues with the soybeans I scout in the same area. Two spotted spider mite populations have increased over the summer and some of the soybean leaves have developed a mottled yellow appearance. If damage increases unchecked the soybean leaves will eventually wilt, turn brown, and fall off. However, after finding the mites and their characteristic damage we had a miticide applied which kills the adults but not the larvae. Because of this I’ll continue scouting these mite infested fields, and the other subsequent soybean fields, as we perform our weekly checks looking for soybean aphids and additional spider mite outbreaks.

Checking the underside of a soybean leaf with a hand lens to look for 2 spotted spider mites

Checking a soybean plant for soybean aphids. The treatment threshold we use is 250 aphids/plant. So far the most I’ve found is 25.

Toward the end of the week, I service several farms in the area around Fillmore and Houghton before heading to Sandusky to check corn for a large dairy. I also have some soybeans in this area and have recently started to find another issue in soybeans, that being Downey. I have not yet taken the plant pathology course (that’s coming this semester) so my knowledge of plant diseases is fairly limited. However, after consulting my CCA (Nick), our company scouting handbook, and of course Google, I believe its Downey Mildew. It appears as yellow spots on the upper leaf surface and a grey “fuzz” on the underside of the leaves located directly below the yellow spots. After finding the Downey Mildew we recommended a couple different options, one being to take soybeans out of the crop rotation schedule for cycle and the other being to moldboard plow the soybean fields to bury the infected residue before planting soybeans again. The additional duties of the last couple of weeks have been pretty much identical to what was discussed in the last post, “All about Bugs”. Though I especially enjoy the weed identification and management end of crop scouting, the last few weeks have increased my knowledge and interest in insects, diseases, and their management.

All About Bugs

Sweeping for army worms (round 2)

The last couple weeks have been all about bugs. We’ve been scouting for corn rootworm beetles, leafhoppers, and the dreaded armyworm. The armyworms have returned for another round of fun, but this time were ready for them. In anticipation of the second wave of armyworms we have been checking our grass crop fields. I started seeing them last week and they are still very small (about the diameter of a toothpick) and around a quarter inch long. The first time the armyworms appeared I could find them by looking at the ground on my hands and knees, but due to their small size we have been using our sweep nets to catch them. So far, I’ve found a handful of fields above threshold with this new infestation and I’m sure we’ll be keeping an eye out for increasing worm populations.

We’ve also been doing the weekly checks for leafhoppers in alfalfa fields. I discussed this in previous posts, but the basic idea it is to sweep the field each week after it has been mowed to see if the leafhoppers are above threshold. Once the population of leafhoppers is evaluated and if it is found to be above threshold the field will be treated or mowed. If the population is lower than the threshold I return to sweep the field again next week. The other insect we have been busy looking for is corn rootworm adult beetles. This type of scouting requires three successive visits to the same field over a three week period. The corn field must be from 80 – 100% tasseled and we look at three groups of ten corn plants and count the total number of corn rootworm beetles hiding in the collars of the leaves. I have to admit this is my least favorite scouting for a couple reasons. One being that I am arachnophobic and there are often all kinds of spiders and webs in the tall corn. The other being the tons of pollen and anthers that rain down on you all day and make you itch like crazy! But its all part of the fun I guess .

scouting for rootworm beetles in the sunshine

Last week we had a little celebration for WNYCMA. The bosses, David and Dierdre DeGolyer, had a nice picnic for all the employees and several of our farmer customers to celebrate 25 years of service to area farmers. We all gathered and had a good meal with steaks, hotdogs, and all the different deli salads you could imagine. Then David gave us a little history on WNYCMA and several longtime employees talked about the various changes in crop production and management over the years. We also talked about current issues such as the effect the drought is having on the corn and the second coming of the armyworms. After that, we went to a soybean field and did some training on identifying 2 spotted spider mites and their symptoms commonly found in soybeans. With the long period of dry weather the mites are also an issue this year. It was a nice event and was interesting to see how much a local business has grown in the last quarter century.

Mid summer scouting

Checking alfalfa height with markings on my sweep net

The corn scouting season is on the downward slide. In fact, I will be finishing the early season corn scouting by next week. It will be interesting because I will scout young ,2 leaf corn and shoulder-height tasseling corn during the same week. The fields which are tasseling will be scouted for corn rootworm beetles to get an idea of the pressure this pest will put on the next year’s corn crop. It has been an eventful corn scouting season with plenty of weeds to identify from seedlings on up to mature plants. I only saw a few escapes, or weeds which were not completely killed by the herbicide programs. Many farmers also had armyworms moving into their corn fields (often from neighboring grass crops) and defoliating corn. Most of these fields bounced back without having to be replanted.


Recently, I’ve been in soybean fields performing weekly checks for soybean aphids. I know a little bit about these insects due to a project I did for an IPM course that I took at Alfred State, before I came to Cornell (Go Pioneers…and Big Red!!!). The WNYCMA threshold for treatment of these little green aphids is 250 insects/plant, but so far the most I’ve found is 15/plant. As usual, I’m also on the lookout for weed escapes and any other flushes of weeds which may have gotten past the residual effects of the herbicide in the bean fields. I’m responsible for scouting about 300 to 350 acres of soybeans and so far they look good and some are starting to flower.


Soybean aphids are the little green dots above my thumb

Today, July 10, I started scouting drilled sorghum fields. Scouting the sorghum is a much like corn scouting except the populations are much higher. This farm, located in Pennsylvania, planted 103 acres of sorghum over a two day period. So far, the weed pressure looks low and the small plants appear off to a good start. I saw some bird damage, where the whole plant was plucked out, but no army worms. I understand that a second infestation of armyworms is possible, but I hope that doesn’t happen. The farmers are sick of these bugs and one made me laugh when he told me that his spray bill is ” just about as much as the national debt”. The other big project going on right now is looking for potato leaf hoppers in alfalfa. They have often been above threshold especially in the new alfalfa seedlings. I’ve become very accustomed to identifying “hopper burn”, a yellowing on the margins of the alfalfa leaves where the hoppers are feeding. The weed pressure is noted and we take crown counts of the alfalfa by counting the number of alfalfa crowns that fall within a square foot ring. Hopefully, we will get some rain soon to keep all the crops growing and to cool me off.

Working on my tan while sweeping for leaf hoppers in an alfalfa field

Crop Scouting with Western New York Crop Management Association

The corn scouting season is in full swing here in WNY. This summer I’m working for Western New York Crop Management Association. The organization offers crop scouting, nutrient management, and CAFO (confined animal feedlot operations) planning as well as other services.  I’ve been assigned crop scouting responsibilities on 12 farms in the southern tier of western New York and Northwestern Pennsylvania. My boss at WNY CMA is Nick Youngers. Nick is a Certified Crop Advisor and manages over 12000 acres of field crops. He also supervises a technician and another scout besides me; he is a very busy guy.

My new wheels for the first half of the summer!

In the last couple weeks I’ve scouted corn, soybeans, alfalfa, and grass-legume hay fields. I enjoy working with field crops and I’ve gotten plenty of opportunities to spend time in many local farmers’ fields. In the field I stage crops, take populations, and evaluate the weed, insect, and disease pressure. The early season corn scouting is the most intense and time consuming scouting we do. Corn is very susceptible to the various pests, especially when it’s young, so we put in the hours during this time of year.  We have all worked 70+ hours, six days a week since mid-May. The scouting thus far has really sharpened my weed seedling identification skills. I’ve found plenty of all “the usual suspects” such as lambsquarter’s, pigweed, ragweed, quackgrass and annual grass weeds.  We have also seen plenty of armyworm infestations in grass hay fields and corn. The little fellas defoliate the corn and often just leave a whorl of leaves. Many fields had cutworm infestations and these insects “cut down” the corn seedlings. These stand out because the cut down corn plants take on a bluish wilted appearance.

Corn plant damaged by cutworm

For all of these pests we use a variety of Integrated Pest Management (IPM) concepts, but for the scout the primary concern is if the pest is above or below threshold. The weeds, and insects, and disease pests have differing ways which we evaluate if they are above or below threshold. Though we try to promote farmers to use IPM to save money, reduce resistance, and reduce potential environmental issues, some farmers view their reports and treat their infested fields immediately, regardless of pest density. After a field has been treated, I return to the fields after the reentry period has been met to verify the pests have been controlled.
The scouting process is repetitive, but this repetition has given me the opportunity to really get good at identifying common pests and has also given me time to build rapport with the farmers and find out what their common pests are on their particular place. All of the farmers I work with have been very friendly and supportive during this learning process that is the early season scouting.  As the growing season progresses, I look forward to doing different tasks in the various crops and learning as much as I can. It’s hard to believe that June is nearly over already, summer and the growing season are flying by!

Wild mustard in corn

Skip to toolbar