STRAIGHT FROM THE HORSES MOUTH

Duane A. Lienemann, UNL Extension Educator, Webster County May 15, 2010 Edition I have to tell you, I really like this kind of weather. You can’t beat this environment for sleeping and working comfortably on lawn, garden or even (drum roll please) spring cleaning. Unfortunately our crops probably do not like this same comfortable weather. I addressed the yellow wheat last week and suggested that it was highly probable that the lack of growing degree days (warm weather and photosynthesis) was likely the cause along with perhaps some problems with nutrient uptake and perhaps some nitrogen abnormalities. Now we are seeing more of the same in our other crops. More Yellow: That should not be too big of a surprise to us however, considering that the same environment that is affecting our wheat, will of course affect other crops as well. The difference has been that corn and soybeans have for the most part just emerged. Yes, some of the seed has been in the ground a long time. Can you blame those developing plants for staying under cover? The rain this past week ended up being a Godsend. It is no secret that many of our planted acres were crusted over, and I might add about as thick of a crust as I have seen in many years. Corn and beans were having trouble breaking through and there weren’t many options to break that crust. The rain was exactly what the crop doctor ordered. I know that a lot of embryonic plants and farmers were all breathing a sigh of relief. Now we have some funky things going on in those fields. I have seen varying heights of corn plants in the same row from just emerged and yellow to 4 inches tall and perhaps a pale green. The good news is, that a lot of producers who were worrying about replanting, probably won’t have to now. The bad news is that right now some of the fields look a little rough, but I can assure you that with some warm weather and open skies you will see dramatic changes and an evening up of the plants. What amazes me is that the soil temperatures are still pretty cool, but germination seems to not be hindered too badly. When corn and bean plants stay that long in the soil and go through some stress, I always am a little concerned about susceptibility to some insects like grubs, cutworms and wireworms as well as some diseases. Farmers may want to check their fields periodically for these pests and make decisions accordingly. Bird Cherry Oat Aphids: While we are in pests, you may want to check your wheat for small dark colored aphids. These critters are called Bird Cherry Oat Aphids and the bad part is that they carry a virus called Barley Yellow Dwarf which shows up as stunted wheat with yellow, reddish and even purplish leaves. It is usually found in fields that are adjacent to areas with volunteer wheat. A producer from over by Guide Rock brought in a specimen this past week that showed the classic symptoms. I have not seen too much of it this year, but it would not surprise me to see it several areas throughout South Central Nebraska. If your wheat has it, there isn’t much you can do as it is too late and a fungicide or any other treatment other than good growing conditions won’t help. Save your money on that one. The conditions are such that you can expect to see some diseases in wheat and other crops. It doesn’t hurt to be proactive and keep an eye out, especially right now with wheat, with the flag leaf waving and newly emerging heads. Crabgrass and Grub Control in Lawns: One thing about cooler soil temps is that our window of opportunity for putting on crabgrass control on our lawns has expanded. If you have a lawn that is prone to crabgrass infestation it probably isn’t too late to still put on a preventative, pre-emergent herbicide. It also helps to maintain a dense, healthy turf and mow at 3-3.5”, letting grass compete with crabgrass. How about those grubs that are showing up in the lawns right now? The best advice here is to simply ignore white grubs found now. However, if you need to take out some aggression, and feel a little better, two bricks hit together works pretty good. You do need to however control the next generation. The best means are by using preventive insecticides like “Merit”, or “Mach 2” which are best applied between mid June and early July. If you want to get at them right away or you don’t want to wait that long, you can use products like Scotts “GrubEx” which contains the insecticide “Acelepryn”, which can be applied as early as late May or early June. Ugly Red Bumps on Maple Leaves: I have had several samples of maple leaves brought in to the office that really are creepy looking. While ugly, this anomaly on the leaves wouldn’t in reality hurt much other than your pride or the aesthetic value of the tree. These bright red bumpy growths on the top of maple leaves are the result of Maple Bladder Gall Mites. Most likely you had adult mites overwinter beneath the bark and bud scales on the trees. As the tree started to leaf-out they moved to the newly developing leaves and started feeding. The pouch-like galls (bladders) develop in response to this feeding activity. At first, the galls are green but gradually turn red and then black. Adults deposit eggs in the galls as they feed. Ultimately, the adults and their offspring will leave the gall in search of newly forming leaves and continue the cycle. Mite activities drop off as summer heat arrives. I have more information on this insect in my office if you are interested. Cedar/Apple Rust: Another creepy looking thing is the orange colored appendages hanging on cedar trees. This is Cedar/Apple Rust and is more damaging to apple trees than to the cedars. There is a relationship between cedars and apple family trees causing it. I have more info on this disease in my office if you would like to learn more. You can also go to http://extensionhorticulture.unl.edu/ for lawn, garden and tree questions and tips. The preceding information comes from the research and personal observations of the writer which may or may not reflect the views of UNL or UNL Extension. For more further information on these or other topics contact D. A. Lienemann, UNL Extension Educator for Webster County in Red Cloud, (402) 746-3417 or email to: dlienemann2@unl.edu or go to the website at: http://www.webster.unl.edu/home