Editor's Note: This is a synopsis of the article last week from Peter Thomison, with the pictures attached. I've included a bit of the information to "explain" the images, but if you want "The Whole Story," please refer to last week's CORN Newsletter (2016-20).
On a typical midsummer day, peak pollen shed occurs in the morning between 9:00 and 11:00 a.m. followed by a second round of pollen shed late in the afternoon. Pollen grains are borne in anthers (Fig. 1), each of which contains a large number of pollen grains. The anthers open and the pollen grains pour out in early to mid morning after dew has dried off the tassels. Pollen is light and is often carried considerable distances by the wind. However, most of it settles within 20 to 50 feet.
Figure 1: Pollen shed begins in the middle of the central spike of the tassel.
Pollen shed is not a continuous process. It stops when the tassel is too wet or too dry and begins again when temperature conditions are favorable. Pollen stands little chance of being washed off the silks during a rainstorm as little to none is shed when the tassel is wet. Silks are covered with fine, sticky hairs, which serve to catch and anchor pollen grains (Fig. 2).