Extension Update by Jenny Rees

Crop Update: The heat has really pushed crops along. Grateful for the reports of some rain! It’s really important to know your soil moisture levels and work for the balance of not stopping too soon vs. leaving the field too wet going into the fall/winter. The following information comes from the NebGuide: Predicting the Last Irrigation of the Season found at: https://go.unl.edu/k74n:

• Corn at Dough needs 7.5” (approximately 34 days to maturity)
• Corn at Beginning Dent needs 5” of water (approximately 24 days to maturity)
• Corn at ¼ milk needs 3.75” (approximately 19 days to maturity)
• Corn at ½ milk (Full Dent) needs 2.25” (approximately 13 days to maturity)
• Soybean at beginning seed (R5) needs around 6.5” (approx. 29 days to maturity)
• Soybean at full seed (R6) needs 3.5” (approx. 18 days to maturity)
• Soybean with leaves beginning to yellow (R6.5) needs 1.9” (approx. 10 days to maturity)

Alfalfa and Wheat Expo: Southeast Nebraska farmers can sharpen their management strategies at the inaugural 2021 Southeast Nebraska Alfalfa and Wheat Expo. The inaugural Alfalfa and Wheat Expo is scheduled for Thursday, September 2, 2021, in Crete at the Tuxedo Park Exhibition Building. The Expo will begin at 8:00 a.m. with refreshments and exhibitor booths. The educational program starts at 9:00 a.m. and ends at 3:30 p.m. Hosts and local Water & Integrating Cropping Systems Extension Educators, Nathan Mueller, Gary Lesoing, and Melissa Bartels said more diverse crop rotations are both underutilized and undervalued. Integrating alfalfa and winter wheat into the crop rotation can provide a critical tool to mitigate extreme weather, improve soil health, increase corn and soybean yields, combat troublesome pests, increase flexibility in manure management plans, and more. This new expo will help farmers prepare to grow these crops for the first time or fine-tune the skills of experienced alfalfa and winter wheat growers. Speakers and panelists will address important issues for southeast Nebraska farmers and allow for great one-on-one discussion with local private industry exhibitors and sponsors. The Expo is free to attend including lunch, but pre-registration is requested by August 31. For more info. and to pre-register, please visit https://croptechcafe.org/alfalfawheatexpo or call the Saline County Extension office at 402-821-2151.

Renovating Lawns in the Fall: August 15-September 15 are the best times to seed cool season grasses. This resource, Improving Turf in the Fall at https://go.unl.edu/rz9z is a great one to walk you through renovation depending on your situation. Some lawns can be easily improved by adding fertilizer this fall.

Sarah Browning, Extension Horticultural Educator shares, “Late summer or fall fertilization of Kentucky bluegrass and tall fescue lawns is the most important time to fertilize these cool season grasses. Fertilizer applied now promotes recovery from summer stress, increases density of thinned turf, encourages root and rhizome growth, and allows the plant to store food for next spring’s growth flush. On older lawns, those that are 10 to 15 or more years old, that typically need only two fertilizer applications a year, make the fall application in late August or early September using fertilizer with all or some slow-release nitrogen. On younger lawns, two fertilizer applications during fall are recommended. Make the first one in late August or early September, and the second in mid to late October. For the first one, select a fertilizer with all or some slow-release nitrogen. For the later application, use a fast release nitrogen source so plants will take it up before going dormant.”

Other lawns can be improved via overseeding or total renovation. If overseeding is needed to fill in thinned areas but more than 50% of good turf remains, mow the existing grass 2.5” tall to make the soil preparation easier. For lawns needing total renovation, start with a glyphosate (Roundup application) followed by waiting at least 7-10 days to kill the lawn. Mow dead vegetation as short as mower goes to then prepare the soil for planting.

To prepare the soil for seeding, it’s helpful to aerate the lawn making three passes. Watering a day or two beforehand can make the aerification easier. The full seeding rate for turf-type tall fescue is 6-8 lbs./1,000 sq.ft., and 2-3 lbs. for Kentucky bluegrass. When overseeding into an existing lawn, the seeding rate can be cut in half. Drilling the seed is perhaps easiest for a total lawn renovation. Otherwise, use a drop seeder to apply the seed (not rotary ones as the seed is too light to spread evenly). Make sure to seed half the seed north/south and the other half east/west to ensure even distribution. Then lightly rake in the seed to ensure seed to soil contact. Starter fertilizer is helpful for new seedings where the total phosphorus is 1 to 1.5 lbs/1000 sq. feet. It’s also important to keep the top ½ to 1” of soil moist as seedlings germinate. Thus, it may requiring watering several times a day the first two weeks, depending on temperature and moisture. As seedlings develop, reduce the watering schedule to allow root development. When the grass is tall enough to mow, reduce watering to only 2-3 times/week with deeper watering. Mowing as soon as the grass allows encourages tiller development and thicker new stands.