All hay is not created equal
This is stacking up to be a challenging year for production of adequate supplies of good quality hay in the Southwest.
Hay fields came out of the long winter and cold spring on the dry side. Then we had very little rain in May, a crucial month for moisture for our hay crop. Once it started raining in June the grass was already starting to head out very short and the alfalfa was stunted. The crop has recovered somewhat but it will still be a below average crop in many areas.
Once cutting got underway in early July the rains kept coming and unless you were lucky, the swaths have been rained on at least once, and in most cases several times. Rain on swathed hay can reduce both yield and quality. Losses are greatest in hay that has partially cured prior to the rainfall.
One study conducted in Wisconsin recorded dry matter losses as high as 22% when alfalfa hay was exposed to 1 inch of rain one day after being cut. Similar alfalfa hay never exposed to rain only lost six per cent of its potential dry matter yield. Alfalfa hay exposed to 1.6 inches of rain over a few days lost 44 per cent of its potential dry matter yield.
In another study in Michigan, the effects of one to seven hour rains where examined on alfalfa hay. Here, dry matter losses ranged from four to 34 per cent, and were greater the longer the rain lasted. Grass hay often will not experience the same degree of loss as alfalfa hay. The majority of yield loss in alfalfa hay is due to leaf loss. Grass leaves are not as easily lost. Most of the studies have shown that there is little impact on crude protein levels when field cured hay is rained on. However, due to the leaching of soluble carbohydrates, acid detergent fiber and neutral detergent fiber levels will increase. This lowers the digestibility of the hay and its overall forage quality.
The studies tend to agree on this issue. Given the same amount of rain, a low intensity rainfall causes more loss of quality than a high intensity rainfall.
Research on alfalfa hay has demonstrated that every inch of rain on hay in the swath reduces its energy content by up to five per cent and digestibility by 10 per cent.
For many of you, instead of having 57 per cent TDN hay, you’re going to have something around 50 per cent TDN with reduced digestibility. Consequently this hay will look a lot like the poor hay we had in 2010. The main problem with the 2010 hay was the low digestibility which limited intake, leading to skinny cows and weak calves. To make matters worse, most stack yards are pretty empty this year so there may not be any better quality hay from last year to help balance the ration.
To avoid the wrecks we saw during the winter of 2010-11, plan now to get a hay analysis done before fall so you know what you’re going to have for feed this winter. Your regional livestock specialist can help you determine how you will need to supplement your hay this winter if you provide a hay analysis.
It may seem a bit crazy to be planning for winter this early but before you know it harvest will be here and weaning will be around the corner. There may be some good opportunities to purchase supplements or additional hay supplies at a discount before demand starts to grow this fall. The way the hay crop is coming off, having a hay analysis this year could be the difference between a profit and a loss.