Continued weather issues: Will spring return?

Tony Nye - OSU Extension

Spring sprang and now Mother Nature is just messing with us. The recent freezes have fried many of our fruit crops, and the continued cold, wet weather is keeping us looking for spring fever again.

For area producers, it is still early, but many have been starting to do some field work and prepare for the planting season. I am not sure the weather is set to change for the good just yet. Looking at extended forecast, it does not look like much will be done for the next couple of weeks. Remember, though, it is Ohio, and there can change at any moment.

Speaking of planting season, projections for crop planting nationally has been announced and I am sure many producers are already aware but for corn, projections for corn planted for all purposes in 2016 is estimated at 93.6 million acres, up 6 percent from last year. If realized, this will represent the highest planted acreage in the United States since 2013, and will be the third highest planted acreage in the United States since 1944.

For soybeans, in 2016 planting intentions is estimated at 82.2 million acres, down less than 1 percent from last year. Compared with last year, planted acreage intentions are down or unchanged in 23 of the 31 estimating states.

As it relates to weather, Ohio State plant pathologist Anne Dorrance reminds producers that cool, wet soils promote the growth of one of the major seed and seedling pathogens of corn and soybean, Pythium. Some of the more than 25 different species of Pythium are particularly favored by these cooler temperatures. Since the soil is moist, zoospores, which overwinter are germinating. When the soils become saturated, they will form a structure called a sporangium which forms the zoospores.

What is unique about this group of pathogens compared to watermolds is that these spores will then swim to the roots; they are actually attracted to germinating seeds and growing roots. When seeds are planted into cool soils, and we have some low temperature nights, the seeds themselves can be injured. This then serves to attract more zoospores – quite a system all in favor of these cool, wet-loving pathogens.

Plant in as close to optimum conditions as possible. Don’t try to beat a major storm front – in Ohio that is a classic set-up for replant conditions. Keep monitoring those soil temperatures to ensure the best jump start for this seed. If in doubt, go back and look at the receipt for that seed, this is a huge investment for the overall farming inputs. You only want to plant once.

Well-drained soil, and seed treatments with one or more of the ollowing: metalaxyl/mefenoxam, strobilurin, or the new fungicide ethaboxam will all protect young seeds/seedlings, but to a point. Too much cold, long periods below 50 F and extensive saturated soils can overwhelm the system. Resistance to Phytophthora sojae (warmer temperature oomycete) is well studied and well known for all of the varieties that you purchase. It is not known how resistant the varieties are to Pythium spp. There are just too many to test.

Finally this week, Anne Dorrance reminds producers it is not too late to sample for Soybean Cyst Nematode this the spring, especially in years where the ground thaws early.

It is becoming increasingly important in Ohio to know your numbers. Sounds like a cholesterol warning doesn’t it? In the case of SCN, less than 500 eggs per cup of soil and keeping it under 1,000 is what we need to shoot for on some fields. Non-detectable levels are like gold.

If you haven’t tested in a while, here are some guidelines of fields to be sure to target:

1. Fields which are consistently low yielding, always below the county average

2. Continuous soybean fields

3. Fields with a healthy crop of purple dead nettle, shepherds purse, or planted to a legume cover crop. These can all serve as additional hosts to SCN and especially with a warm winter there will be some increase in nematode numbers.

If you have yield maps, especially for no-till farmers, target the low yielding pockets. SCN will stay in that one pocket, but the pocket will get larger over time with no-till. With cultivation, the pocket will get larger in the same direction that you till.

Only two labs in Ohio will accept samples:

Spectrum Analytic Inc, Washington Court House, OH 43160. Phone number is 800-321-1562.

The other lab is the OSU C. Wayne Ellett Plant and Pest Diagnostic Clinic ($15/sample), 8995 E Main St, Bldg 23, Reynoldsburg, OH 43068. Phone number 614-292-5006.

Tony Nye is the state coordinator for the Ohio State University Extension Small Farm Program and has been an OSU Extension Educator for agriculture and natural resources for 28 years, currently serving Clinton County and the Miami Valley EERA.

Tony Nye

OSU Extension