Richard Taylor, Extension Agronomist; rtaylor@udel.edu
I received the following inquiry via email this week and thought that other hay producers might be concerned with regrowth this year. “My ‘Corvallis’ teff purchased locally is not coming back well and I have numerous dead areas following first cut. One planting is on droughty sandy soils and has 60-70% stand. Another planting is on a low lying wetter sandy soil and has 70-80%. Some of the stand loss is on the headlands but there are also bare areas throughout the fields. This is my third year growing teff and what is growing seems to be regrowing slower than normal. I’ve also heard of two other teff growers who are having similar problems. Have you heard of this problem or have any ideas what is happening?”
I not surprised that teff might be having a bit of trouble growing this year. I think two things might be contributing. Although it seems that the news broadcasters keep trying to convince us it’s been a hot summer, in actuality, we haven’t had nearly as many accumulated heat units as we normally receive. At least that has been my impression of the summer of 2013. For the rate of growth of a C-4 warm-season annual grass such as teff, I think heat units would be very important.
The other factor is the amount of sunlight that we’ve had this summer. If it hasn’t been hazy and/or misty, it’s been cloudy more days than I can ever remember in a summer. With a lot less solar radiation reaching the teff plants, I would not expect them to grow as rapidly as usual. Teff is not the only crop that worries me as I am concerned that our soybean and corn yields could be adversely impacted by this same factor.
Initially, I was a bit surprised to read that the dry sandy sites had lower stand density than the bottom ground although after thinking about it I should not have been surprised. One of the first years teff was available in our region, a hay producer in western New Castle County grew the crop on some very poorly drained soil. For the most part where lodging was not a concern, teff survived the wet conditions well. The very shallow root system of teff could be responsible for its tolerance of wet feet.
That brings up another factor that will reduce the ability of teff to recover after harvest. Lodging from heavy rains or high winds before harvest can significantly reduce the ability of teff to regrow. The shading created by lodging is a real problem for teff since it can reduce the amount of stored energy reserve that is needed for regrowth. The shading from lodging also results in very few basal leaves remaining active and alive following harvest. With less reserve energy and few if any leaves left alive at the crown of the plant, regrowth can fail. Another factor we have observed is that when producers allow teff to mature so that it begins to flower, lodging and subsequent regrowth often was a significant problem.