9 articles tagged "Climate and Weather".

Soil temperatures are critical for seed germination and are closely related to occurrences of some early season soilborne disease and pest problems on vegetable crops. Plant vegetable crops after the soil is warm enough ensure good seed germination and fast crop establishment. The figures below show daily average soil and air temperatures at  recorded at six locations (Figure 1) in Indiana from April 25 to May 8 that maybe helpful in assessing soil conditions for planting across the state. More information regarding recommended soil temperatures for vegetable planting can be found in the articles https://www.hort.purdue.edu/ext/ho-186.pdf  and https://vegcropshotline.org/article/seedcorn-maggots-and-wireworms/      

I have never had as many questions about how to use MELCAST as I did in 2015. The interest in this program is growing both here in Indiana and nationally. Read on to find out how to apply fungicides according to the weather and perhaps save money in the process. MELCAST (MELon disease foreCASTer) is a weather-based disease-forecasting program for cantaloupe and watermelon growers developed By Dr. Rick Latin at Purdue University. Instead of using a calendar based fungicide application program where one applies fungicides every 7 to 14 days, the MELCAST program lets growers apply fungicides when the weather is most conducive to disease. The diseases for which MELCAST may be used for are: Alternaria leaf blight, anthracnose and gummy stem blight. Details are listed below or in the extension bulletin, Foliar Disease Control Using MELCAST, BP-67-W. Download the bulletin at http://www.extension.purdue. edu/extmedia/BP/BP-67-W.pdf or contact Dan Egel for a[Read More…]

Winter is coming to a close in about a month, and the coldest of the days should be behind us at this point. Here in Indiana, El Nino usually points to a warmer, drier kind of winter.  With the past El Nino being considered one of the strongest on record, how much did the warm Pacific Ocean affect Indiana? The temperature and precipitation graphs around the state look somewhat similar to Figures 1 (Columbus) and Figure 2 (Lowell). High temperatures generally trended unseasonably warm right around the winter holiday, December 23 or 27, and around February 2. During both periods, record warm temperatures were set depending on location within the state.  The southwestern portion of the state had a four day record shattering streak of warm temperatures, while the more impressive warmth was experienced in February at some more northern locations (Figure 2). Going around the state, high temperatures this[Read More…]

Red: primary. Gold: continguous. Source: http://www.fsa.usda.gov/Assets/USDA-FSA-Public/usdafiles/Disaster-Assist/Disaster/ALL_CROP_CY2015.pdf

​ On August 12, 2015, USDA designated 88 counties in Indiana as natural disaster areas due to heavy rainfall since May. The four counties not designated disaster areas are LaGrange, Perry, Spencer and Steuben. Farm operators in the ‘disaster’ counties are eligible for low interest emergency loans from the Farm Service Agency, provided they meet certain qualifications and eligibility requirements. Farmers have eight months, or until April 12, 2016, to apply for the loans. Contact your local USDA Service Center  for more information about loans and to learn about additional programs available to help recover from disaster, or visit http://disaster.fsa.usda.gov. ​ Source: USDA Office of Communications http://content.govdelivery.com/accounts/USDAOC/bulletins/11421cf​​

Vegetables such as this watermelon may become sunburned if lack of foliage cover exposes the fruit to excess sun and heat. (Photo by Dan Egel)

​Loss of foliage due to poor growing conditions or disease can cause fruit to be exposed to the sun. Hot temperatures and direct sunlight can lead to areas of the fruit that appear bleached or sunburned. Sunburned fruit may not be marketable. To reduce the probability sunburned fruit, every effort should be made to maintain foliage throughout the season. Early wet weather encouraged foliar disease and recent hot, dry weather may have restricted foliar development. Orienting vegetable plantings to minimize damage from the prevailing winds and providing windbreaks such as strips of rye or wheat may help to reduce sunburn. Several products are available that are labeled for use as a preventive for sunburn. These products may be broken into two groups: kaolin (clay) based products and calcium carbonated based products. Kaolin based products include Surround®. Some Surround® products are labeled for use as sunburn protection, while others are not. For example,[Read More…]

Note that the Wabash River is visible through the break in the trees.

​With the record-setting rainfall we’ve seen over the past month, flooding of fields is very widespread (Figure 1). Fields that have experienced flooding present growers with difficult management choices. Flooding is defined (per FDA) as the “flowing or overflowing of a field with water outside a grower’s control.” Flooding is associated with streams, creeks, or ponds that overflow their banks and cannot be controlled. The FDA considers food contacted by flood water to be “adulterated” and not fit for human consumption. Due to microbial and other concerns, produce cannot be harvested and sold into the public food supply once it contacts flood water. Frequently, only a portion of a field is affected by flooding. If only part of a field is affected and flood water contacts the edible portion of the crop, growers should manage the contaminated crop so that it does not affect uncontaminated crops. To protect uncontaminated crops,[Read More…]

​High rainfall amounts lead to loss of nitrogen from the soil. Sometimes the loss is great enough that a crop will benefit from additional nitrogen application. This article will describe how nitrogen is lost and factors to consider in deciding whether to apply extra nitrogen. There are two main ways nitrogen is lost from wet soils. Nitrogen is lost to the air by denitrification. Denitrification occurs in saturated soils when there is little oxygen in the soil. In the denitrification process, nitrate is broken down by bacteria to form oxygen and volatile nitrogen compounds including nitrous oxide and nitrogen gas. These volatile compounds move into the air and nitrogen is lost from the soil. Denitrification is common on heavier soils. In Indiana, saturated soils lose 4% to 5% of their nitrate nitrogen for each day they are saturated. Nitrogen is lost below the root zone of the crop by leaching.[Read More…]

Seven day observed precipitation (in.) ending June 23

​Much of the state has seen excessive rains in recent weeks (Fig. 1). When soils are saturated vegetable crops suffer. This article, slightly revised from its original publication date in July 2003, describes and explains problems that are likely to occur.   Vegetable crops become stressed in waterlogged soils. Aboveground wilting, yellowing and death of leaves, and epinasty, or downward curling of leaves and stems are all responses to what is happening to roots. If we had a window into the soil we would see roots stop growing and root tips die due to lack of oxygen. Wilting occurs because roots in waterlogged soil do not conduct water as well and lack of new root growth limits water uptake, while the aboveground portion of the plant may continue to grow for a time even after the root has stopped. The root system just cannot supply water fast enough to prevent wilting.[Read More…]

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