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Recent heavy rains have caused problems for farmers in south central Illinois; we’re seeing phytopthora root rot affecting soybean fields. Phytophthora is a soil-borne water mold common in fields that are saturated and not well drained. Phytophthora can affect the plant at two different stages; one specifically targeting the stem. This happens before the root system is developed and during the VE/emergence stage. We call this the seedling blight phase, which can cause damping off. The second affects the roots of larger, more developed plants. The fungus infects the roots and grows into and along the root cells of the plants, which is what we are seeing right now.

Phytophthora root rot can be fairly easy to detect when dealing with the root rot stage. The roots will be a discolored brown and root nodulation will be minimal, causing a chlorotic nitrogen deficient plant. The disease will move up the stem from the soil line and dark to reddish brown lesions will continue up the stem. The dead tissue quickly becomes soft and water soaked. The plant will soon look wilted and chlorotic (yellowing) leading to death of the plant. Sometimes a few plants will be affected and other times large areas of the field will be affected. This disease generally affects individual plants within a row (one out of seven to 10 plants may be affected.) Infected plants will eventually wilt and die, with the leaves still intact but delivering devastating yield loss. 

If your fields are affected by phytohphora root rot this year, there’s really nothing you can do about it this growing season. However, growers can plant varieties with phytophora resistance along with seed treatments to protect seedlings from the disease in future years. Stine has an outstanding lineup of Rps 1a/1c/3a phytophthora root rot-resistant varieties in its lineup for 2019. Additionally, our Stine XP seed treatments contain fungicides to protect your seed investment from unwanted soil-borne pathogens. Stine XP Complete, Stine XP-F&I and Stine XP-F all boast resistance to phytophthora spp.

To learn more about phytophthora root rot detection and prevention, contact your local Stine sales agronomist.

When you’re out scouting your fields this summer, look for a small beetle with a shiny copper-colored body and a green head and thorax. These little pests are Japanese beetles, and they’re making their way across the Midwest.

Japanese beetles can usually be found feeding on gardens, trees and shrubs, but they’re also known to pop up in corn and soybean fields. My region in Illinois has an increased infestation of Japanese beetles this year earlier than ever, causing concern for area corn and soybean growers who worry how the pests will affect yield. Here are a few things you should know about Japanese beetles and how you can treat your fields this year:

• Japanese beetles are in the order Coleoptera and the family Scarabaeidae. The beetles start as eggs and hatch into larvae in the soil during the winter. As larvae, they moult to become C-shaped grubs. As temperatures rise in the spring, the grubs break hibernation and within four to six weeks pupate into adults.

• Where there’s one Japanese beetle, there may be hordes of beetles nearby. Japanese beetles do not travel alone as they feed in clusters. This is a result of a pheromone the beetles emit that attracts other beetles as they feed on the leaves of plants.
  
  
• They typically pop up around late spring/early summer. Check corn silks and leaves for signs of the insect, as well as the leaves and flowers in soybean fields. The beetles feed on these parts of the plant, which can ultimately affect pollination and yield.
  
  
• If you don’t immediately see the beetles, their damage can often times be detected on the plant. Silk “clipping” can be spotted on corn plants, and holes in leaves or shredded (or defoliated) leaves with brown edges can be signs of the pests. In soybeans, Japanese beetles typically feed on the leaf tissue between veins, which leaves behind a lace-like skeletonized appearance.
  
  
• If Japanese Beetles are detected, they can be controlled through insecticides such as Sevin or pyrethroid insecticides.
  
  
• The University of Illinois Department of Crop Sciences notes that the threshold of Japanese beetles in soybeans should be based on the percentage of leaf defoliation. The university recommends that treatment should be considered if 20 percent of the leaf is defoliated before bloom and pod fill and if pre-bloom soybeans have around 30 percent leaf defoliation.
  
  
• In corn, the university recommends that insecticide treatments should be considered if silks on the plant have been clipped to half an inch or less or if pollination is less than 50 percent complete. The university also recommends treatment if more than three beetles can be found per ear. 

For more information on Japanese beetles and how to detect and prevent these insects from robbing yield, contact your local Stine sales rep. 

Dust off your notes from 2016 and put on your walking boots. It’s time to start planning for early-season crop scouting. In many areas throughout the South and Midwest, growers are well into planting. But there’s still a lot of work to do right after planting — early-season crop scouting. Here are a few tips to get you started.

1. Start early — earlier than you may have planned. First off, start scouting before emergence. Even if it’s not quite time for the crops to surface, something could be lurking below ground that may affect the seedlings. Below-ground insects such as seed corn maggots and wireworms can be present, and diseases such as Pytophthora root rot and Pythium root rot can be problematic before plants emerge. Areas where soil compaction may be an issue should be assessed to ensure plants aren’t having trouble emerging from the surface soil. And areas where high moisture is a concern need to be assessed to determine if replanting is necessary. Chances are if you detect these issues early, there’s still time to save your yield.
2. Walk the fields. Whether you manage 200 or 2,000 acres, it’s far too much land to scout from the window of a pickup. Growers need to walk each field to detect problem areas. You can’t determine if you need to roll out a fungicide, insecticide or a post-emergent herbicide just by scouting the edges of your fields. Really get into those fields, dig in the dirt where certain areas may concern you and take soil samples if you need to.
3. Once-overs won’t cut it. Crop scouting is a season-long job. Don’t expect a once-over after emergence to do the trick. I recommend growers walk their fields at least twice a week. Weeds can pop up in a matter of days which can change your yield outlook, and Mother Nature is unpredictable. Make crop scouting a weekly part of your job, all the way up to harvest.
4. Review notes and take new ones. If you took notes from 2016, you should know what areas to check this year. Prior seedling diseases, past weed resistance issues and past insect infestations can help you develop a plan for managing your field after emergence. Scout those problem areas from 2016, and take new notes in 2017 as the season progresses. 
5. Ask for advice. As a farmer, you have a wealth of information about agriculture at your disposal. But there’s nothing wrong with asking an agronomist for input if you struggle to pinpoint a problem area in your field or understand why your plant stand isn’t where it should be. And stay in contact with your agronomist throughout the growing season, as they likely can tell you when other growers in your region experience problems with their fields. Stine has a number of agronomists on hand, ready to answer your questions throughout the planting, growing and harvest season. Find your local Stine agronomist here.