Forage for Knowledge

However, this data was collated early this week and so represents what was happening last week and a lot can happen in a week.

I was on farm in Wiltshire yesterday with a group and growth rates were tight around the demand line.

We then dug a small hole in one of the host's paddocks and the root zone had no moisture. The previous week's growth had been 44 and the latest 28, so in their case moisture had run out.

This week’s growth data from the sampling farms averages about 44 with a range of 24–99. Previous spring average national growth would be 70+.

So, the story going forward is potentially two different stories depending on rain. I am sitting in my office on Wednesday morning (21 May). Outside it is raining and we have probably had 20 mm of rain overnight, and good rain at that, nice and steady so it will be soaking in and hitting the roots.

Looking at the forecast for where I live in Devon, out of the next seven days there is forecast five days of light rain. This makes me very confidant that in the next week we will have enough rain to kick growth back in and back conservatively to 60+ kg DM/ha per day and if I am being bold 70+.

The temperatures are not above 20ºC, so really good growing potential. My suggestion in this scenario with an average cover of 2100–2200 (as most sampling farms have) is to aim to graze at 2800 kg DM/ha entry cover, hit residuals and with 60+ growth aim for a 20/21 day round and cut surplus.

My reasoning is we are in or approaching the heading period when the plant goes reproductive. The result of this is increased stem and seed heads.

Intermediate ryegrass heads in the last two weeks of May and late heading are the first two weeks of June. If we add a week either side of that for all to head this means for the next four weeks we will have plants heading.

Before the head emerges the plant is still highly digestible; post-heading digestibility drops. Perennial ryegrass only heads once (so if your cows graze a paddock, for example, two days before heads emerge the seed head is eaten and gone and the plant will not head again).

So if we have the growth to support it a 20/21 day round will take you through the  heading period and you will minimise the effect of the plant going stemmy and heading, then we will be back into leafy highly digestible grass.

If you are unlucky and you don’t get significant rain or you do and you have a drying wind and temperatures above 25ºC (perennial ryegrass struggles above 25ºC), try to maintain average cover. Slow your round and enter supplementary feed to feed cows and do it gradually.

If you are having to feed silage and temperatures are mid 20’s plus centigrade, feed this in the cooler part of the day. Cows start to suffer heat stress around these temperatures and eating increases heat production in the cow.

By slowing your round and maintaining average cover when it does rain the platform will respond and recover quicker than if you do deck everything. An average cover below 2000 is starting to slow recovery, it will rain and when it does you need quick recovery.

Try avoiding heavy covers as above 3000 kg DM/ha it will probably be stemmy and heading plants which will be a struggle to hit residuals and will be low feed quality.

It may be an idea to pre-mow so that you utilise all you have but above 3000 entry, then success at clearing is lower.

If you do use this method to utilise, make sure there is plenty of water on hand as this diet will be very dry and will mean cows drink more.