PLEASE BE CAREFUL DOING FIELD WORK IN THIS HEAT - BRING EXTRA WATER AND STAY HYDRATED. There are no trophies for being too tough to quit and getting heat exhaustion!

1. Field Observations

Lots of corn either tasseled over the weekend or is currently going to tassel, which means we will now begin to track GDD from tassel for corn silage harvest forecasting (see section 2). Up to this point, GDD accumulations have been anywhere between the 30- and 15-year normals. But obviously this all changed this week, so stay tuned. 

The knapweeds are flowering, so here is a reminder of knapweed species ID and current mgmt options. And remember, biocontrol weevils are only available for spotted knapweed (and I've yet to see a single spotted knapweed in our area - only the other half-dozen-or-so species, mostly meadow and brown). To manage knapweed w/o chemicals, mow them now, as they're beginning to flower. In grass hayfields, spray the regrowth with 0.625 oz/ac Cimarron Plus + 8 oz/ac Banvel + 16 oz/ac 2,4-D Ester. As with milkweed, reigning in knapweed is a multi-year process…. (and remember to fertilize your fields!)

2. Growing Degree Days as of July 20 (See: Climate Smart Farming Growing Degree Day Calculator)

Growing degree days (GDD) are calculated by taking the average daily temperature and subtracting the base temperature for
development of a given organism ((High + Low)/2 - base temp = GDD). For corn silage, we are using base 50/86, as corn
development starts at 50 degrees F and ceases above 86. Check your location and planting date:

I'm having déjà vu from last year. As soon as the corn tasseled, the temps have skyrocketed. As these forecasts for two CNY locations suggest, look for temps over the next week to be near/above record highs. ~30% above the 15-year normal:

3. Pest & Disease Monitoring

A. Western bean cutworm (WBC), true armyworm (TAW) and fall armyworm (FAW) in corn.

This week, insect numbers remained low in most places aside from moderate levels of pea aphid in alfalfa, which is seldom damaging to the extent where sprays are economical.  At tasseling, the window of risk for WBCW largely closes, and the cornfields where we saw the highest populations (still low by damage-causing standards) were just beginning to tassel:

B. Potato leafhopper in alfalfa. I couldn't make it to a few of my usual fields, but those I swept were still below threshold. I'm seeing a fair number of aphids, but tons and tons of insect predators that seem to be keeping things well under control so far: