We've just had a few very hot and windy days, but the kikuyu is still growing rapidly on most of the farm. However, on the deep sands, it is showing moisture stress and is starting to slow down in its recovery from grazing. We are still green and almost all paddocks have a thick cover of plant residue on them.
Worm egg tests continue to come back with all zero's, which is very pleasing from the high burdens we had to contend with from an error with trade sheep late in 2019.
In previous blogs, I mentioned we had taken plant tissue tests of the kikuyu in December 2020, and blood tests in two groups of lambs. I've yet to see the results of the blood tests, but have been verbally told what was found, and it is interesting.
Despite topdressing with high rates of selenium, cobalt, copper, zinc and molybdenum, the copper levels in the lambs are below where they need to be, most likely because the molybdenum levels in the plants is too high. The levels of selenium, cobalt and zinc in the lambs are good. Because we've raised the soil pH with the liming, that has made the molybdenum highly available in the pastures, which causes copper to be less available in the plants, and in the sheep. So I've been adding some copper to the water trough network and will fix the pastures this coming season to have higher copper levels. I will keep monitoring the blood in the sheep to check how we are going and to make sure we don't overdo the copper.
For those who don't know, raising the soil pH increases the availability of selenium and molybdenum, but decreases the availability of cobalt, manganese and zinc. Copper is also decreased, but nowhere near as much as occurs with zinc and manganese.