By definition, the last effective bloom date is the day in which the probability of a new flower developing into a boll and making its way into the basket declines to below 50%. Since it is unlikely (probability less than 50%) that fruiting positions which develop after this date will contribute to yield, end-of-season insecticide termination and defoliation recommendations for our area are based upon protecting/managing those positions which will be flowering Continue reading
Tyson Raper (Cotton and Small Grains Specialist) and Frank Yin (Systems Agronomist)
Sulfur (S) deficiencies have been becoming more common in cotton fields in recent years. This is in part due to a reduction in sulfur emissions from manufacturing plants and diesel fuels. Nitrogen (N) and S deficiencies are commonly confused- particularly late in the season. Although both cause chlorosis of leaf tissue, the mobile nature of N within the plant results in deficiency symptoms first appearing low in the canopy. In contrast, S is very immobile in the plant and, as a result, S deficiency symptoms first appear in new growth near the top of the plant. Continue reading
A rough start for many of TN’s cotton acres has turned into a decent summer for the majority of our acreage. This is very evident when looking at accumulated heat units noted at the West Tennessee Research and Education Center in Jackson, TN. As you can see in the below graph, we are quite a bit ahead of the last two years on accumulated heat units. Warm temperatures in mid/late June and timely rains have Continue reading
Tennessee cotton is finally ‘growing off’. Still, here on the 3rd day of July, it appears few farms will reach the coveted ‘bloom by the 4th’. Although the environment has played a dominate role in maturity up to this point, management decisions emphasizing earliness have been particularly useful in 2015. This marks the third consecutive year in which managing for earliness has a marked effect on crop maturity by early July. 
On the heels of last year’s delayed crop, Dr. Owen Gwathmey and I began discussing potential benefits of managing a cotton crop for earliness and the management practices which encourage timely maturity and harvest with colleagues both within and beyond the University of Tennessee. We have summarized these thoughts in the attached Guide to Earliness Management in Short-season Cotton Production (PB1830). Continue reading
Rains and warmer temperatures have promoted rapid growth over the past week. Now that the root zone has expanded and N uptake has increased exponentially, expect very rapid plant growth in areas which have adequate moisture as we move into flowering. For those who have not applied an early shot of a plant growth regulator (PGR), you should consider doing so very soon. Several points should be considered when attempting to regulate growth in 2015. Continue reading
Although most early planted upland corn looks pretty good for the year, I have had a number of discussions about about streaky, yellow corn and applying more nitrogen. Continue reading
With snow in the forecast, I hope you find some warmth in our hot-off-the-press 2015 Tennessee Cotton Quick Facts Publication (W 319) which is now available online. New this year are digital hyperlinks to all full-length UTIA publications. Simply click on the grey boxes or related QR codes describing the publication in which you are interested and your browser will do the rest. Keep losing your guide or tired of carrying paper guides around? Open this document with the reader on your mobile device (if Apple, your iBooks app) to have a digital copy at your fingertips at all times. Hyperlinks will still work!
I’ve recently received several calls concerning N applications on wheat. Although this cold front has made it easier to get across wet fields, it is still early for the first split in a late winter/early spring split-N application approach. To make the most of the first split, target ‘spring greenup’, or the period in which wheat breaks dormancy and begins to grow rapidly (typically Feekes 3 or Zadoks 25). Delaying applications until this point can help ensure the applied N is available to the developing crop by reducing the potential for N loss. The current N demand of the dormant crop Continue reading
