Ron..NE ILL..10/48 - 9/16/2007 10:45 I read a lot about tissue tests here on NNAT. I'll guess we're not very good farmers right around here, I don't really know any neighbors that utilize tissue testing. We don't. Soil testing...yes! Let me know if you or your area uses tissue tests as a common practice. So, re. tissue tests. Are the results skewed by nutrient uptake factors? Roots-disease-insects-pesticides? Absolutely! Dry weather, compaction, nematodes, soil insects, and other things affect the crop's ability to take up nutrients, and thus tissue levels. A lack of vigor in early season due to wet conditions and / or cold temperatures can haunt you all year. I have fields with very good soil fertility with crops growing on them that display nutrient deficiencies because of poor uptake. Nematodes and compaction are my main challenges down here, and we often have to compensate by setting higher nutrient goals and foliar applied nutrients. I have found that foliar N, K, B, and Mn are pretty effective, but foliar N & K are only supplemental to a good soil program. I see people wanting to foliar apply P and Ca to correct problems sometimes, but am not too sure that it's any good. Sometimes we think that foliar Ca seems to help set blooms on vegetable crops, probably so.
I assume that practitioners test both corn & beans. That shows the nutrients lacking? Or oversupplied? Lacking, I'm sure, but am not quite smart enough on the oversupplied question. Some nutrients compete with others for space in the plants.... Will different varieties exhibit different results? I am sure they will, as there are some that are more shallow rooted by nature than others, for example. Will different lot #s exhibit different results? We know that particular varieties have more vigor than others, for example, and I can see that poor early season vigor would affect the plant's ability to capitalize fully on avaiable nutrients and water. Vigor, however, is not only a trait of variety, but varies from lot number to lot number as much or more than warm germ.
Will climatic conditions skew results? Yes. Almost all of these problems are increased in the presence of other stress conditions.
If your tested crop is corn & next yrs crop is beans, how do you utlize results for next yrs planning? I don't know! A lot of difference there! Are these fair questions? No! UNFAIR to expect a consultant to have so many real answers to real questions! | 
Tissue tests?
