Field Crop News

REGISTER NOW FOR THE ROCK SPRINGS AGRONOMY WEED TOUR - JULY 15, 2004 32nd Annual Agronomic Weed Management Research Tour at Penn State - July 15, 2004 at the PSU Agronomy Research Farm, Rock Springs, PA (Meet at the Agronomy Farm, Rock Springs, Rt. 45 west of State College). A number of experiments will be showcased and available for viewing including many of the new corn herbicides (Lumax, Camix, Keystone, Cinch, Steadfast, Epic, Equip, Option, etc.) plus the latest information on herbicide resistance, weed competition, and cover cropping and weed management research. In addition, you can hear about Roundup Ready alfalfa and its status including controlling in a rotation. Finally, looking for alternative weed control, come see how vinegar and clover oil (Matran II) are working as weed control tools.

Agenda:
9:00 am - Registration and introductions
9:30 am -12:00 noon - Tour
12:00 noon - 1:00 pm - Catered lunch

Registration for this event will be $15.00 and includes lunch and a tour book. Please pre-register one week prior to the event (by Thursday, July 8) with Lisa Crytser by phone (814-865-2543), fax (814-863-7043), email (lac8@psu.edu), or mail (registration form) so we can accommodate luncheon needs.

PENN STATE AGRONOMIC FIELD DIAGNOSTIC CLINIC 2004 - JULY 21 AND 22

The dates and topics for our annual Diagnostic Clinic have been set. As in the past, the Clinic is a one-day event from 8:45 am to 4:30 pm. Unlike past years, this year's event will be conducted at the Penn State Ag Progress Days site near Rock Springs, PA. The Clinic will be held on Wednesday, July 21 and then repeated on Thursday, July 22, 2004. The topics include:

Registration forms are being mailed (and emailed), so look for yours soon to register and to get additional information on each of the topics. The cost of this year's Clinic is $45/person ($65 after July 13). If you do not receive a registration form within a couple of weeks and would like to attend, contact Lisa Crytser at (814) 865-2543 or email- LAC8@psu.edu. Or visit our website at http://cropsoil.psu.edu/extension/clinic.htm

For additional information or comments about the Diagnostic Clinic contact Dwight Lingenfelter at (814) 865-2242 or by email, DXL18@psu.edu.

WEATHER OUTLOOK

Unlike May, June 2004 will average very close to the long-term mean temperatures across the state. Most sections will be a little below the seasonal average. Precipitation through the first three weeks of the month has been above normal. Rainfall totals have exceeded average in the southern tier with the heaviest amounts in the Laurel Highlands and the eastern part of the Susquehanna River valley. Wind and hours of sunshine are running near to a bit above normal which has helped with daytime drying conditions, especially in the east.

Rainfall will become more scattered and intermittent. Some sections, perhaps most, should only notice one or two days with showers in the next ten. Initially, temperatures will average a bit below normal, due to cool mornings. The northern counties should experience several mornings with readings near or below 50F. Commencing about the first of July, a steady warming trend is expected that may peak with a period of hazy, hot and humid conditions centered around the Independence Day holiday weekend. A more ordinary number of thundershowers are expected after July 5.

The outlook for July and August still indicates above normal temperatures and below normal rainfall with August tending to be rather hot and dry.

PRODUCTION

CORN DEVELOPMENT AND THE WEATHER

Over 80 percent of our corn crop is rated good to excellent with most areas receiving regular precipitation through June. In general, I think our yield potential is excellent for some of the early planted corn, although it is still early to forecast the final yield with much certainty. On the positive side, on many fields we have full canopy coverage here at the summer equinox, so our crops will be taking full advantage of the long June days and radiation. Also, the development of our early corn is tracking well ahead of normal, with the possibility of some tasseling by early July, which should help avoid any maturity issues and start to help provide some more insurance against late season drought periods. These factors make me think that we may be on track for some record breaking yields in some areas and good farm average yields as well.

Some fields with only preplant N applied may experience some late season N deficiency due to N leaching and higher crop N demands. The frequent precipitation could lead to shallower rooted crops on some soils which could make the crop more susceptible to root lodging or drought stress if the rain quits for an extended period. In the short term the soil moisture conditions should enhance recoverability to any rootworm injury that has occurred.

Later planted corn seems to be developing at an average pace, with the recent cool evenings and may still be more at risk for some maturity and drought issues late in the season. Corn in some areas with wet soils is experiencing some stunting due to saturated soil conditions. In one test plot we abandoned, the corn between the drainage tile lines was about 12 inches shorter and yellow compared to normal corn right over the lines. This corn showed symptoms of root rots in the crown and the mesocotyl.

PEST MANAGEMENT

POISONOUS PASTURE PLANTS AND LIVESTOCK

Well it's almost July and that means the potential for reduced pasture growth and a greater potential for overgrazing. Despite the fact that we have had moist conditions for good pasture growth thus far, we have already received some calls concerning potential livestock poisoning by weeds. Livestock may be forced to graze on weeds that normally they would not, or they may eat weeds out of curiosity. Scout your pastures and remove these weeds before they cause livestock health problems. Keep in mind there are numerous poisonous plants that could invade an area or pasture. Many plants contain potentially poisonous substances that may be toxic to livestock if consumed. In addition, certain plants may be problematic because of mechanical irritation when eaten, photosensitization, and disagreeable tastes or odors in meat, milk or milk products. If you suspect livestock poisoning, call your local extension educator or veterinarian immediately. If death occurs, the stomach contents should be examined for consumed herbage. Identify the suspected plants and remove livestock from the grazing area until all poisonous plants have been removed or destroyed. Table 1 lists only some common weeds and their poisonous properties; many other plants can be toxic to livestock.

Table 1. Selected poisonous plants of the Northeast (Information adapted from Fishel 2000; Hardin 1973; and Hill and Folland 1986 and D. Wolfgang, PSU)
Common name	Problem/symptoms	Toxic ingredient - toxicity dosage
Bouncing bet	Leaves and stem - delayed for several days; depression, vomiting, abdominal pain, diarrhea	Saponin - amount equivalent to 3% (dry wt.) of sheep wt. killed within 4 hr.
Buttercups	Leaves and stem especially in flower. Dried hay loses toxicity - anorexia, salivation, weakness, convulsions, breathing difficulty, death	Protoanemonin - toxicity reported to vary with species, age, and habitat. Generally 1-3% of body weight necessary.
Cherry, black	Leaves (wilted leaves are worse), stems, bark and fruit - anxiety, staggering, breathing difficulty, dilated pupils, bloat, death	Cyanogenic glycosides - Less than 0.25 lb leaves (fresh wt.) can be toxic to 100 lb animal. Leaves from several small to mid sized branches are sufficient to kill an adult animal.
Clover species	Vegetation - Hairballs; Sweet clover: nose bleeding, anemia, abdominal swelling	Coumarin with sweet clover - varies
Fern, bracken	Entire plant - Dullness, fever, bleeding, loss of appetite, and salivation	Glycoside thiaminase - Cattle fed 50% bracken for 30 to 80 days was toxic. Others report that only 20% of diet for 30-60 days was toxic.
Garlic, wild	All plant parts - tainted milk and meat.	Only toxic in large quantities
Hemlock, poison	All plant parts - nervousness, salivation, vomiting, diarrhea, weakness, paralysis, trembling, dilation of pupils convulsions, and coma, death	Coniine and others (pyridine alkaloids) - 0.5 to 4% (fresh wt.) equivalent of cattle wt. is toxic. In horses, 0.25% of body weight.
Jimsonweed	Entire plant (seeds are most toxic - Thirst, mood swings, convulsions, coma, death	Solanaceous alkaloids - 0.06 to 0.09% (dry wt.) equivalent of animal body wt. is toxic.
Locust, black	Leaves (especially wilted), seeds, and inner bark - Causes weakness, depression, anorexia, vomiting and diarrhea	Phytotoxin robin, glycoside robitinm - bark extract and powder in amount equivalent to 0.04 - 0.1% of animal wt. toxic to horses. Cattle 10-times more tolerant.
Milkweeds	Entire plant - depression, muscle tremors, spasms, bloat, difficult breathing.	Glycosides and galitoxin - 0.3 to 0.6% of body weight.
Mustards	All parts (especially seeds) - oral and gastrointestinal irritation, shaking, salivation, abdominal pain, vomiting, and diarrhea.	Thiocyanates, irritant oils, and nitrates (large quantities generally necessary for toxicity)
Nightshade species	Vegetation, unripe fruit - loss of appetite, salivation, weakness, trembling, paralysis	Solanine - toxic at 42 mg/kg (LD50). 0.1 to 0.3% of body weight.
Pigweed species	Foliage (worse in drought) - kidney disease, weakness, edema, rapid respiration	Nitrates nitrate oxalates, unknown - 0.5 to 1% of diet. Sheep, hogs, and young calves most susceptible.
Pokeweed, common	Entire plant, especially roots - gastrointestinal cramps, weakened pulse, respiration, salivation	Phytolacctinm - 10 or more berries can result in toxicity to humans. Unknown for livestock, but perhaps 100-200 berries/1000 lb.
Snakeroot, white	Leaves and stem - constipation, loss of appetite, salivation, rapid respiration. Toxin passes through milk (milksickness).	Trophine alkaloid - varies from 1 to 2% of animal body wt. after 2 weeks. Toxin cumulative.
St. Johnswort	Flowers and leaves - photosensitivity which leads to redness of muzzle, around eyes, and around white hair.	Hypercin - uncertain

Agents Corner

SOUTHEAST

Everyone is hoping for a stretch of warm and dry weather very soon, because there's still plenty of hay to be made. Some isolated fields of orchardgrass need to be cut, and the majority of the timothy is still standing. Corn is reaping the benefits of the recent heat and moisture, and is looking excellent. Most fields appear to be at about 7-8 leaf stage, with sidedressing all but complete. Soybeans are much more variable, the earliest fields have canopied over, with Roundup applications, and I drove past a farm last evening with the drill parked outside, just waiting for the soil to dry off enough to plant. Over the last 10 days all oats have headed out, and there are reports of widespread head scab in wheat.

SOUTHWEST

With the 4-6 inches of ran distributed over the southwest corner of the Commonwealth from 6/11 to 6/17, everything pretty much came to a halt. Corn in the lowland fields, and even some upland fields began expressing stress by turning yellow, stunted growth and a general unhealthy appearance. Unsprayed oat fields and even winter small grain fields turned green, from the encroachment of annual and perennial weeds. Not a good situation.

Early planted corn is 36" and taller as of this writing and looking well. Later planted corn has some holes in the stands and significant variability of appearance. Also some corn fields never were sprayed with herbicides which will reduce some yield potential issues, even after they are sprayed.

Second cutting alfalfa meadows also began expressing some stress due to leafhopper activity. And speaking of hay meadows, unharvested first cut fields did various versions of a "lay down" dance, due to the heavy rainfall or flooding. Disc type mower conditioners will be coveted by those who don't have one.

This year, once again, the only farmers who made real progress with first cut harvest were those with the ability to ensile the forage. But the weather beginning on Saturday, June 19 encouraged farmers to mow hay, even though soils and soil compaction is an issue.

Farmers who intensive graze pastures have been blessed with ample moisture to keep the forage growing, but animal traffic is causing some soils issues on some paddocks.

All in all, since we don't know what a "normal" season is, it might be appropriate to declare, the southwest is either having another partially or totally abnormal season. Not sure which.

IN THIS ISSUE:

Mark Your Calendar

Weather Outlook

Production

Pest Management

Agents Corner

Mark Your Calendar

PENN STATE AGRONOMIC FIELD DIAGNOSTIC CLINIC 2004 - JULY 21 AND 22

WEATHER OUTLOOK

PRODUCTION

CORN DEVELOPMENT AND THE WEATHER

PEST MANAGEMENT

POISONOUS PASTURE PLANTS AND LIVESTOCK

Agents Corner

SOUTHEAST

SOUTHWEST