Features Agronomy Soil
Copper cropper

When I first came to Alberta many eons ago, a wet growing season meant there
was potential for very good wheat and barley yields. Unfortunately, many of
these good potential cereal fields lodged. Sometimes they showed-up with a lot
of ergot and produced unexpectedly low yields and frosted bran. Yet, there was
never any frost. What was the problem that Elston Solberg, Doug Penney and I
solved? Copper deficiency!

In wet seasons, we have shallow rooting of cereals, which is where we have
the higher levels of soil organic matter and lower copper levels. Also, higher
yielding cereals need more than normal copper levels. What happens is that we
can run into severe copper deficiency along with yield and quality collapse.
The confusing thing is that there is no response to added copper fertility in
these very same copper deficient soils during dry years. This is because cereal
roots move down into the subsoil where there is usually adequate copper for
the lower yielding crop.

If you suspect soil copper levels are low and your crops look good to very
good before heading, apply copper fertilizer right away or at least before the
late boot stage. That is the prime time for fungicide application. If you have
doubts about copper or have been listening to agronomic 'know-no's', put in
some trial strips of foliar copper fertilizer.

Remember, copper cannot be applied after head emergence, since it makes a bad
situation (copper deficiency) worse. If you have or suspect soil copper deficiency,
act immediately to avoid those lodged cereal fields (yes, copper deficiency
causes lodging) that produce low yields of ergoty, frosted bran sample grains
of cereals. -30-

*Dr. Ieuan Evans is a Senior Agri-Coach for Agri-Trend Agrology.