El2-Corn Talk, Lancaster Farming, Saturday, October 18, 2003 Getting The Most Out Of Com Demonstration Plots John Rowehl, CCA, Grain Cumberland County Extension Com test plots offer all sorts of information to grow ers, only part of which is re flected in the yield results book that is handed out at the conclusion of the growing sea son. Observations made in sea son give you a chance to look over other characteristics im portant to your variety selec tion decisions. Compare the relative heights (both plant and ear) among com hybrids. High ear placement increases the risk of stalk lodging later because of the higher center of gravity. Check the relative stalk size among com hybrids. Thicker stalks are generally correlated with better standa bility later on. Split a few stalks and check the thickness ‘Beer Can’ Ears Make An Appearance Greg Roth Professor Of Agronomy Penn State Recently, Extension Agent Del Voight has reported two separate fields showing the blunt-ear syndrome or “beer can” ears in Lebanon County. These are ears that are characterized by a relatively normal husk covering, some silk balling, and noticeably stunted cob develop ment. The result is a short ear with maybe 10 rows of kernels instead of the normal 35-40 rows and usually a short segment of cob that has not been pollinated because of to the failure of some silks to emerge. We don’t really know what causes the problem, but it appears to be more prevalent following springs that had some cool tem peratures that may have caused some chil ling stress to the plants. I expect we’ll see more of these this year following the cool spring we had. In some of the past years where I’ve seen this, there has been a weak relationship with some hybrids. In some cases it’s scattered in the field, but in a few cases nearly the whole field can be affected, with serious effects on yield. Dr. Bob Nielsen, my counterpart at Pur due University, has a graduate student who is studying this problem and is trying to document the situations where the problem has occurred. Bob and his student have pre pared a downloadable survey form, www.kingcorn.org/research/beercan/ Fieldlnfoform.pdf, for folks who are willing to share the background on a field showing these symptoms. If you find a field, please consider sharing the data on it with Bob. of the rind. If you walk variety test plots closer to harvest, you can also compare hybrids for their relative stalk health and integrity. By late August or so, you can pinch lower stalk intem odes and check for stalk rot development. Hybrid differ ences for stalk rot develop ment often reflect differences for tolerance to stresses in general. Look at the relative leaf health among com hy brids. This year in particular has been favorable for a number of leaf diseases to get started. If you plant a lot of no-till acre age, try to find plots that are also no-till. In no-till test plots, pay particular attention for hybrid differences for gray leaf spot infestation. If you find a disease you are not fa- Plastic Hugger Corn Head is Designed To Look And Feel Like Steel. • Three position dividers • T-pin and hair clip convenience • Easy transport and storage Alrville. PA FARMER’S EQUIPMENT & SUPPLY, INC. 3524 Delta Road 717-862-3967 Columbia Cross Road. Pi Annvlllo. PA COLUMBIA CROSS BHM FARM ROAD EQUIPMENT RD 2, Box 62 Rt. 934, 2 miles N. of Annville 570-297-3873 717-867-2211 Elizabethtown. PA Taiii'cDmam cadm HERNLEY’S FARM FARM EQUIPMENT ? u .S E 2095 South Market St. School Road 717-367-8867 717-933-4114 Carlisle. PA CFS - CARLISLE FARM SERVICE 260 York Road 717-243-4419 MASSEY FERGUSON* miliar with, ask your exten sion agent, crop consultant, or sales agronomist to identify it for you. Another facet of leaf health is the so-called “stay-green” characteristic that reflects a hybrid’s ability to simply re main viable longer than oth ers. Generally speaking, “stay green” hybrids have a higher tolerance to stress factors than others. If little leaf disease is visi ble, yet some hybrids’ leaves are “shutting down” while those of comparable hybrid maturities are remaining green, the latter are likely “stay-green” hybrids. Shuck a few ears and compare the rel ative ear size among com hy brids. Kernel row number is strongly determined by a hy brid’s genetics. Number of #l SOURCE FOR PARTS j Jm. QUALITY PARTS AGCO Improve your performance in the field. Call us for prices. Chambersbura. PA Greencastle. PA Oakland Mills. PA CFS - CHAMBERSBURG MEYERS PEOPLE’S SALES & FARM SERVICE IMPLEMENTS, INC. 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