Fall Armyworm in NZ Maize: Four Years of Research
Four years since it was first detected in New Zealand, researchers and growers now know much more about management of maize pest fall armyworm (FAW).
Maize silage is an ideal supplement to use because when cows eat maize silage they leave more pasture in the paddock. This article provides a few tips on feeding higher rates of maize silage.
1. Test your maize silage. It is always a good idea to test your maize silage to determine the drymatter content and feed value. It’s even more important this year as it has been a far-from-normal growing season and plant drymatter levels varied greatly even within paddocks. Knowing maize silage drymatter content and nutritive value will enable you to feed budget and plan feed-out rates more effectively.
The best way to sample is to take handfuls from across an open stack face. Alternatively a closed stack can be cored, but make sure you plug the holes with salt and seal the cover. Samples should be submitted to a laboratory as soon after collection as possible. Place them in a plastic bag, burp the air out and store them in a cool place. Avoid couriering samples at the end of the week.
2. Introduce maize silage slowly. While animals whose rumens have had time to acclimatise to maize silage can be fed high rates, it is never a good idea to feed too much too quickly. Start at 1-2 kgDM/cow and gradually increase the feeding rate over time. Take care when moving from one stack to another, especially if they contain different hybrids or have different starch levels.
3. Watch maize silage wastage. Good feed-out management is important. Keep the silage face tight and remove all loose silage on a daily basis. If you have used Pioneer brand 11C33 or 11CFT and your maize silage has fermented for a minimum of 30 days, you can feed out maize silage up to one day in advance. In all other situations feed out as close as possible to when the cows will eat the silage. Remember there is a feed energy loss associated with any silage heating.
4. Watch calcium intake. Especially if you are milking or wintering cows which are in the early dry period on lower calcium feedstuffs such as palm kernel, maize silage, grains or straws. Calcium is the major mineral in the body with 98% of it contained in the bones and teeth. It is essential for muscle activity, blood clotting, nerve transmission and enzyme function. Low calcium status increases the incidence of milk fever and calving difficulties. Ideally the diet should contain 0.6% calcium. If your diet contains less consider supplementing with limestone (calcium carbonate).
Your veterinarian, nutritionist or local Pioneer brand products representative can help determine appropriate feeding rates. Limestone supplementation in the late dry period is not generally recommended.
• Ian Williams is a Pioneer forage specialist. Contact him at This email address is being protected from spambots. You need JavaScript enabled to view it.
