I spent this week in Auburn, Alabama, for the annual Board meeting of the Southern Cover Crops Council. This group was formed in late 2016 after the Southern Cover Crop Conference in North Carolina; follow the embedded link for more information about the 2016 conference and note that one of our tasks at this meeting was to start planning a conference for 2019!
Since our formation, we have been busy developing cover crop resource guides and a selection tool. These are being evaluated and will be LIVE later this year! The Southern region spans a wide range of climates, physiographic regions, and production systems; we have our work cut out for us to develop information for all of these combinations BUT we also have a dedicated team of growers, researchers, extension specialists, NRCS agents, and many others who are contributing to this cause.
We did take a break for a tour of the Old Rotation in Auburn, and saw some equipment from the USDA ARS National Soil Dynamics lab. The Old Rotation examines the impact of fertility, cover crops, and crop rotation on cotton yields--cotton is a major crop in Alabama. Here are some photos from the tour. Stay posted for updates on when our resources will go LIVE!!!
First things first: here is a talk that I gave at the Wheat Field Day at the University of Kentucky Research and Education Center in Princeton. It deals with using wheat as a cover crop compared to cereal rye. Most of it addresses this issue from a weed management and planting perspective.
Now... In case you hadn't noticed, it has been warm. (Or, in my opinion, HOT for early May.) The National Weather Service says that we haven't set many daily maximum temperature records, but the first half of May was the second warmest on record in Lexington. Check out the crop progress report for both corn planting and winter wheat heading--look how far behind we were in late April and then look at how steep the lines climb in early May. We had pretty ideal planting conditions, until the unsettled weather this week brought some heavy rains. Inches of rain in a short period soon after planting usually isn't good--soil washes away and nitrogen applied to soils without plants is lost more readily. All the more reason to use those cover crops to keep your soil covered--just make sure you're timing termination to what your planter can handle!
All that worry about our cold winter and spring, and look where we are now... almost two solid weeks of temps in the 80s and warm nights. We're done planting our corn trials at Spindletop, and even have some soybeans in the ground--earlier than usual.
In the spring, I get a lot of questions about when to terminate cover crops like cereal rye. As usual, my answer is -- it depends! The main things it depends on... what do you want to get out of the cover crop? Another things to consider-- what kind of planter do you have, and how well can it deal with residue? I talked recently at the Wheat Field Day in Princeton, KY, in part about this topic and will post the video once available.
Here are some photos from our cover crop trials. All of these plots were planted on 10/5/17 using a mixture of oats and cereal rye. I estimate the cereal rye seeding rate at approximately 30-40 lbs seed/acre. The oats winter-killed, leaving the cereal rye.
If you want maximal weed suppression in the next crop, that comes from having more cover crop biomass. However, you must be able to deal with that biomass! If you are not equipped to plant through that residue, you are better off terminating earlier. Gaps in your stand will lead to less crop competition, and opportunities for weeds. If your main cover cropping goal is to keep the soil covered and return some organic matter, AND you are not ready to plant into residue, then terminating earlier is a good option. If you choose to terminate late, we recommend starting on a small piece and trying it out first...
One of the best parts of being in academia is working with students. I just had the pleasure of serving on Mitchell Richmond's PhD committee. Mitchell did an in-depth research project on chemical topping in tobacco. After an exciting (well, for us, maybe not for Mitchell) 3-hour conversation about plant physiology, agronomics, economics, gene regulation, and many other topics, Mitchell Richmond is now Dr. Mitchell Richmond! (Well, he will be once the graduate school confers his degree.) Mitchell has already started a position with the Canadian Tobacco Research Foundation in southern Ontario. Congratulations to Dr. Richmond! PS to all future doctoral candidates--be sure to provide your committee with donuts, coffee, and snacks for a better defense experience :)
The short-term impact is that we can't get into the field. We've had a lot of rain this year (and a little snow). Our UKAWC site has measured over 20" of rain at Spindletop Farm since January 1, 2018. We average 40" a year... This spring has, for the most part, also been cooler than average.
Upshot: it's wet. And it's been cool. Cover crops are growing slower, weeds are slower to emerge (though I saw common lambsquarters, giant ragweed, and marestail emerging in late February after a warm spell AND they're all still alive). See some photos below for differences in cereal rye growth between this past winter and previous winters...
One thing we can do in this weather? Get some horticultural therapy in a high tunnel! Our group has a project with Dr. Krista Jacobsen in the Horticulture Department, and colleagues at the University of Tennessee and University of Georgia. High tunnels are a big investment, producing valuable real estate inside! And, depending on location and the type of tunnel, the environment is favorable for crop growth year-round, so most growers keep crops growing in them continually. This can be hard on the soils. Our project examines (1) some novel cool and warm season cover crops that might fit into short windows between cash crop production and (2) how growing winter cover crops provide nutrient cycling and weed management services.
Today, we buried some bags of weed seeds to examine how our incorporated cover crop residue influences weed seed decay. We also transplanted tomatoes! Stay tuned for all of these results...
And with that means field work! We will be out sampling cover crops soon, and thinking about burning them down in advance of corn. Corn gets planted early in the bluegrass, and we're hoping to plant in mid-April. That means killing off the cover crop by the end of March to avoid any issues with the corn.
Here are two cover crop field days in southern Illinois for those of you in that part of the woods--I met Nathan Johanning last month at the Midwest Cover Crop Council meeting and he talked about growers in this neck of the woods seeing good results after years of using cover crops on some tough soils. We think about Illinois as having nice prairie soils, but parts of southern IL have the same fragipan soils that we have in Kentucky. The first one (in Springerton) will dig a soil pit, which is cool to see if you haven't seen it before! I know it's a busy time, but consider going if the weather is bad and you aren't out in the field!
April 1, 2016 - 9 a.m.
On-Farm Spring Cover Crop Field Day - Jr. Upton Farm, Springerton, IL
April 7, 2016 - 10 a.m.
Spring Cover Crop Field Day – Ewing Demonstration Center, Ewing, IL
Another year is underway, and that means a lot of interesting cover crop webinars. I've posted links to some announcements on the "links" page. All of these webinars are FREE, though some may require registration. There is also a link to a new extension publication from Purdue on annual ryegrass termination. Enjoy!
PS--here is a photo of some frosty oats and crimson clover--still alive as of January 5!
Here is a long awaited update on our current trials. This post will focus on our main cover crop trial at Spindletop that was established in 2014. (We have another cover crop trial in the ground, and a trial looking at weed management in canola. I’ll update you on these trials in a later post, as well as some work we did this summer with chia! (Yes, chia. As in the seed with high omega 3 fatty acids and B vitamins. Also as in ch-ch-ch-chia!))
Summer is in full swing in central Kentucky! This is the first blog entry in a while, so bear with me as I update you on happenings in the program.
First, I’d like to welcome Matthew Allen to the lab! Matthew is a recent UK grad who has been working with Dr. Bob Pearce in his tobacco extension program for the past few years. He brings a great set of skills and a fun attitude to the weed science program. Here he is (on the right) with Dr. Ole Wendroth (on the left) after digging some holes in the field.
There's not a lot going on in the field these days. The Lexington area had a record snow fall of about 10" on February 16 so things are still mostly covered. It's raining a lot today, but we might get another few inches of snow later this week. February 2015 was Lexington's fourth coldest month on record! This cold and wet weather will keep soils wetter going into the spring and might delay planting. Coming from Michigan, it's hard for me to believe that some farmers in western KY can plant corn in early April...