Zinc is a micronutrient essential for plant growth and the reproduction of process of plants. When the supply of plant-available zinc is inadequate crop yields are reduced. Deficiencies of zinc occur on a variety of crops including corn, cotton, pecans, soybeans, vegetables, and citrus fruits.
Zinc deficiency in plants will produce visible symptoms of stress, which might include one or more of the following:
- Interveinal chlorosis (yellowing of leaves between the veins)
- Small and abnormally shaped leaves
- Stunting and rosetting (leaves form a whorl on shortened stems)
In cases of moderate zinc deficiency plants can often have greatly reduced yields without obvious visible symptoms. These deficiencies may remain undetected in the ground for many years unless soil or plant diagnostic tests are performed.
The soil conditions most commonly giving rise to inadequate zinc can include one or more of the following:
- Low total zinc content (such as sandy soils with low contents of organic matter)
- Low pH, highly weathered parent materials.
- Peat and muck
- Prolonged water logging or flooded soils.
An adequate supply of zinc is essential for obtaining profitability. Dolomite ag-lime from Tennessee Valley Resources, Inc., which is a co-product of the zinc mining industry, does contain a substantial amount of zinc as indicated by recent testing from two different labs in the Southeast. The zinc content of Tennessee Valley Resources, Inc., lime distinguishes itself from competing lime sources.
Harry Craft and Roger Sugg, sales agronomists for Tennessee Valley Resources, Inc, assembled the information contained in this report. Roger is a North Carolina State graduate with many years experience as a state agronomist in Eastern North Carolina. Harry is a University of Tennessee graduate and certified crop adviser with many years experience as a sales agronomist for Monsanto.