Treat grasshoppers now, before they mature

Grasshoppers are easiest to control in the 3rd and 4th instar stages. Adult control measures are less effective.

Because grasshoppers move into cropland from untilled hatching beds around field borders and in grasslands, grasshopper surveys should be conducted in these adjacent untilled areas early in the season. If grasshoppers have already invaded the field, they can be sampled to determine if control is warranted. With lots of dry grasses in these hatching areas this year, hoppers will likely move to adjoining crops earlier in the summer.

Sampling /thresholds

Estimating grasshopper densities is difficult and can only be done accurately with some practice. The best method for determining grasshopper density in field borders or hatching areas is to count the number of grasshoppers by using the square-foot method. With practice, this approach can provide good estimates of hopper density. To use this method, randomly select an area several feet away and visualize a one-square foot area around that spot. Walk toward this spot while watching this square-foot area and count the number of grasshoppers that you see in or jumping out of this area. Repeat this procedure 18 times and divide the total number of grasshoppers you saw by two. This will give you the number of grasshoppers per square yard (9 square feet). Counting sites should be chosen at random. Just after hatching, when grasshoppers are small, they will be difficult to see and you likely will underestimate the true hopper density. When sampling, vary the vegetation in the count area, and sample both north and south facing slopes.

To sample for grasshoppers within fields where grasshopper density will be lower, use the same method except visualize and count the hoppers in a square yard area. Because of the difficulty of seeing hoppers in this larger area, counts will be somewhat less accurate. Take 18 samples and divide the total by 18 to arrive at the average number of grasshoppers per square yard.

When the number of grasshoppers per square yard has been estimated, use Table I to determine if treatment is necessary. While sampling it is important to determine the species present and the approximate stage (instar) of the grasshoppers. This is best done by using a sweep net to allow capture of a representative sample of hoppers.

Grasshopper control in cropland

As limited precipitation, scorching temperatures and high winds parch the western Nebraska plains, reservoir inflows dwindle to historic lows and bring little hope for surface irrigation to quench withering crops, a University of Nebraska irrigation engineer said.

Panhandle irrigation districts will deliver water for only 35 to 40 days if current conditions persist, said Dean Yonts, Institute of Agriculture and Natural Resources irrigation engineer at the Panhandle Research and Extension Center in Scottsbluff. Districts are just beginning to release water to canals, hoping to stretch water use for critical crop times.

Irrigation districts will have to strictly monitor and track water use due to the limited supply, Yonts said.

"The problem will be trying to dole out the amount of water available," he said. "Once a grower has used (his or her) allotment, there's no choice but to shut the gates down."

That's what frightens growers like Monty Flock, who farms 400 acres of corn, sugar beets and dry beans near Morrill.

"It's got us scared to death," he said. "I think we're in trouble because what crop we do get is going to be worthless. If they turn off the water in mid-August, our plants won't mature. We'll have nothing to sell."

Faced with above normal temperatures and a lack of rainfall in June, some producers in eastern Nebraska started summer irrigation. (Photo by Brett Hampton)

Drought conditions are most severe in southwest Nebraska, where some irrigation districts will not deliver water at all this summer. That includes the Hitchcock and Red Willow Irrigation District, which draws water from Enders Reservoir, and all districts feeding from Swanson Reservoir, said Susan France, Nebraska Department of Natural Resources' division manager for water rights administration. Several other districts will deliver substantially less water than normal during a shorter time.

Projected allocations range from 4 to 9 inches of water for less than 45 days. Many of these districts normally receive at least 12 inches of water May through September.

Water available for irrigation in the Panhandle and Republican River Basin is limited because of near-record and record low spring inflows that left Colorado, Wyoming and western Nebraska reservoirs well below capacity. Reservoirs in the Republican River Basin are exceptionally low, filled at 29% to 55% capacity. North Platte River Basin reservoirs are moderately low, filled at 52% to 78% capacity, said Mike Hayes, climate impacts specialist at NU's National Drought Mitigation Center.

At Lake McConaughy on the North Platte River near Ogallala, water levels are down significantly but there is enough water for this year's irrigation allocations. McConaughy's water is used by irrigators in the Central Nebraska Public Power and Irrigation District. The major concern for Panhandle farmers is the extremely dry North Platte River, in which inflows are projected to be 30% of average through September, Hayes said. South Platte River inflows are projected to be 25% to 46% of average through September, Hayes said. Minimal inflows mean minimal water for crops.

"In the 44 years I've been farming, I've never witnessed anything like this," said Robert Busch, a farmer near Mitchell. "People don't realize yet what's coming. The economic loss is going to be devastating."

Busch and his son farm 1,100 acres of corn, dry beans, sugar beets and alfalfa. Corn is three weeks behind schedule and only about 4 inches tall, Busch said. To make matters worse, irrigation allocations in the Gearing-Fort Laramie district are expected to be less than 50% of the normal supply, he said. The district receives water from Seminoe and Pathfinder reservoirs in Wyoming.

"In today's environment, you need a good crop every year," he said. "If you don't get that, you're in big trouble."

Sensible water management will be critical to salvaging crop yields, Yonts said. "Water means crop growth," Yonts said. "In many times during drought and water restrictions, our crops haven't been too bad because we tried to use water more efficiently and make changes faster. But I've never been through anything like this." Some growers who rely on surface water for irrigation may already be suffering the drought's consequences. Alfalfa in the Panhandle might only yield two cuttings, reducing yields by as much as 50%, Yonts said. Corn and dry bean yields could drop 25%.

"It all depends on how far the water will stretch," Yonts said.

The limited water supply might require growers to make sacrifices, Flock said.

"We're such optimists," he said. "I think we're making a big mistake by not abandoning a percentage of our crops and stretching the water across what's left."

To help stretch water, furrow irrigators can surge irrigate, or alternate water back and forth for a shorter time to reduce infiltration rates, and use polyacrylamide to stop erosion in furrows to increase water supplied to evenly irrigate fields, Yonts said.

He also suggested shutting off water once it reaches the bottom of a field to reduce unnecessary runoff. Stressing crops at times when water is less critical also may help.

"It's going to hurt," Flock said. "Everybody's going to hurt in the whole valley. Many of us are going to go bankrupt. I'm afraid my wife and I might not farm next year."

Flock and Busch represent many western Nebraska farmers who worry about the future of their farms - a future that seems as fallow as their dusty fields.

"This is the worst I've seen it," Flock said. "We've all been going through times when we're depressed and want to give up. But we know we can't do anything about it."

Shannon Hartenstein
IANR Newswriter

The tour leaves Kearney's Ramada Inn Motel Monday, July 22, and returns there Thursday, July 25.

"Nebraska, Wyoming and Colorado are highly dependent on irrigation water and hydropower generated in the North Platte River watershed, and with the current drought conditions in those areas the tour should be very timely and enlightening," said tour co-organizer Michael Jess, acting director of the UNL Water Center.

In addition to current drought conditions in the watershed, tour stops and speakers will address North Platte River water use, interstate compacts and the recent settlement of litigation between Nebraska and Wyoming, irrigation development, and history.

On July 22 Sharon Whitmore of the U.S. Fish and Wildlife Service will discuss how water releases from Lake McConaughy are used to augment fish and wildlife habitat requirements in Nebraska and members of the Sidney Chamber of Commerce will address irrigation, agribusiness and farming concerns in the area. The first night's stop is in Fort Collins, Colo.

On July 23 buses pass over the Continental Divide and through Cameron Pass en route to North Platte River headwaters at Walden, Colo., and from there north to Wyoming. John Lawson and Ken Randolph of the U.S. Bureau of Reclamation will discuss irrigation and hydroelectric issues at Seminoe Dam, the first of a series of North Platte River reservoirs the tour will visit in Wyoming.

Before overnighting in Casper, Wyo., tour participants also will view Pathfinder, Alcova and Gray Reef dams. As buses head toward Nebraska the following day, Glendo and Guernsey dams will be viewed, including hydro-electric operations at Guernsey and Glendo.

At the Wyoming-Nebraska border buses will stop at the Mitchell-Gering diversion dam to discuss allocation of stream flows among irrigators in Nebraska and Wyoming. From there the tour will visit subsurface drip irrigation research projects at NU's Panhandle Research and Extension Center research plots near Mitchell. Overnight will be at Scottsbluff.

On the final day, local irrigators will discuss conjunctive water use tensions in the Pumpkin Creek valley in Banner and Morrill counties. After a stop at the new visitors center at Lake McConaughy and discussion of UNL dissolved oxygen research at Lake Ogallala, tour buses return to Kearney.

Tour cost is $450 single occupancy or $400 double occupancy. Registration includes all food, motel, and motorcoach expenses. Registration is through the Kearney Area Chamber of Commerce at (800) 652-9435. Registration deadline is July 5.

Other sponsors are Central Nebraska Public Power and Irrigation District; Nebraska Public Power District; Nebraska Association of Resource Districts; Gateway Farm Show; Nebraska Water Conference Council and NU's Institute of Agriculture and Natural Resources, Conservation and Survey Division, Water Center and Panhandle Research and Extension Center.

Steven Ress
Communications Coordinator
UNL Water Center

These small (1/8 inch long), green, wedge shaped insects (Fig. 1) may cause severe damage to alfalfa by injecting a toxin into the plant as they feed. This feeding results in a distinctive yellow or purple triangle shape at the tip of the leaf. First year spring planted alfalfa fields are particularly attractive to and vulnerable to potato leafhoppers, as are fields planted last year. In older fields, these insects are usually a problem on second and third cuttings. Newly developed resistant varieties provide fairly good protection from potato leafhoppers, but alfalfa in the seedling stage may still be damaged. All fields should be scouted because large numbers of leafhoppers can still cause a problem, even in resistant variety fields.

Preliminary estimates to the state Farm Service Agency (FSA) office indicate that more than 300,000 acres in central and eastern Nebraska were damaged by high winds and hail in mid-June thunderstorms.

In Buffalo County, Extension Educator Ralph Anderson reported that damage ranged from minimal to extensive in a storm swath two miles wide that cut diagonally through the county. One field had 90% defoliation of six- to eight-leaf corn and growing points just barely above ground.

"The plants look really bad now. Some of these fields will recover, but there are going to be yield losses."

Such storms are likely to occur for the next six to ten weeks.

For many producers, their options may be limited by previous herbicide selection, timing (in some areas it's too late to replant corn), and wet fields. In many areas, with the hail came heavy rains which have made planting impossible until the soil dries further. Producers will need to consider potential yield loss of the existing crop vs. replanting costs and potential reduced yields. In some cases, the reduced yield of a hail-damaged field may be higher than the potential yield from replanting.

It's almost too late to replant corn for grain and replanting soybeans now could mean up to a 25% potential yield reduction. Estimated yield losses for sorghum are slightly less than for soybeans at this time.

Hail damage assessment and management options vary according to plant stage, however the procedures are fairly similar from crop to crop and stage to stage:

• estimate the growth stage;
• assess the damage; and
• consider options if yield potentials are low.

Growth regulator herbicides often are not recommended when corn is past the 6-inch stage because they can cause gooseneck or brittleness, making the plant more vulnerable to high winds. In sorghum applying a growth regulator herbicide during the fast growth stage can cause the plant to become limp, complicating cultivation.

Sometimes, however, there may not be another herbicide choice. In these cases, direct the application to keep the herbicide out of the whorl. In addition, considering the particularly windy conditions this year, be careful to avoid potential herbicide drift problems.

Over 20 years of research at the Rogers Memorial Farm, east of Lincoln, showed no yield benefit from cultivation of soybeans in no-till, except for one year when there was a shattercane problem. Over the same 20 years, cultivation of no-till grain sorghum averaged about a 7 bu/A yield loss except in two years where it was needed for shattercane control. When needed for weed control, properly selected and timed postemergence herbicides are used on this no-till farm to provide more economical weed control than cultivation. Also, it has been observed that the harvest of soybeans is easier and much cleaner without cultivation.

Various sources put the machinery and labor cost of cultivation around $5 an acre. Paul Hay, extension educator in Gage County, has a "True Cost of Cultivation" handout that puts the cost of cultivation near $28 an acre in dryland, terraced production. This cost includes the machinery, labor, fuel, amount of crop run over during turning, and soil moisture losses.

George Rehm, Extension soils specialist at the University of Minnesota, is showing yield decreases from cultivation in Minnesota on poorly drained soils where some say cultivation is needed to open up the soil. On those poorly drained soils, he recommends ridge plant systems without cultivating every year. (Don't take off much of the ridge at planting time, use Roundup Ready soybeans, re-ridge only in corn).

Cultivation only for the sake of stirring the soil is a waste of fuel, labor, and valuable soil moisture, especially in a dry year like this one. Crop roots near the surface are pruned, crop residue is buried, and the soil is left in a condition that is prone to erosion and crusting. The drying and loosening of the soil reduces root growth near the soil surface, making nutrients in this surface layer less available to the crop. Cultivating wet soil smears the soil layer below the cultivator sweeps, increasing runoff and erosion.

Cultivation for broad spectrum weed control may be needed if the weed pressures are above thresholds such that they would be causing yield reductions. Considering the root pruning and soil moisture loss from cultivation, however, specific weed problems may be more economically addressed using a properly selected and timed postemergence herbicide.

In wet years or under no-till conditions where the residue holds the soil moisture near the soil surface, root pruning is greater since there are more active roots near the soil surface. Cultivation, when performed, should be shallow to undercut the weeds so that they dry down quickly (usually within hours). Operating deep may leave too many weed roots intact in moist soil, leave a furrow which concentrates runoff and accelerates erosion, and dry the soil out to the depth of tillage. That is why the new style cultivators have wide, flat sweeps. Cultivation in ridge plant systems is different and requires barring off disks (cut away disks) for weed control on the sides of the ridge.

Cultivation is an integral part of the ridge plant system and must be performed early to control weeds and loosen the soil without slabbing (root pruning is reduced). A second cultivation (or an irrigation ditching) later rebuilds the ridge and provides some additional weed control. The cost of the cultivation is offset partially by using a band application of herbicides at planting time (or no herbicide at all) and no tillage for next year's crop.

Some people may think the soil needs to be loosened to allow the crop roots to grow. The crop roots are already a foot or more into the soil so stirring the top inch or two won't make much difference. Others think that the corn needs "hilling" so that it stands up. The hybrids used today stand much better than those of the past and rootworm control has improved such that corn doesn't need much propping up. With a proper planting depth (around 2 inches), the brace root formation is such that hilling is not needed, especially when the soil is moist. However, shallow planted corn may not properly form brace roots in dry soil near the surface so hilling may help if the cultivation operation does not further dry the soil.

To save trips across the field, some producers use the cultivator for herbicide application (not advised usually because the cultivation stresses the weeds, making the herbicides less effective), for rootworm or corn borer insecticide application, or for sidedressing fertilizer. These trip-saving approaches may be okay if you can minimize the negatives of cultivation listed above or if you needed cultivation for weed control or ridging. Otherwise, there are other options in many cases to apply the pesticides or nutrients. In a dry year like this one, the soil drying from cultivation needs to considered when performing these "piggy-backed" operations.

When deciding whether to spray, consider the potential for successful weed control and the chance of crop injury.

Huge public response resulted in one of the largest number of comments submitted to the EPA on a specific item. The draft proposal drew 5,249 public comments, of which 1,771 were unique and about 3,500 were the result of information campaigns.

Parts of the proposal drawing the most comments were: proposed wind speed restrictions, application height (especially for aerial applicators), enforcement issues (too vague to enforce), and economic hardships on small farms due to new equipment purchases. Seventy-four percent of the comments were from farmers, agri-business, and commercial applicators.