How to get grass growth back on track

Manawatu agronomist Laura Akers. Photo / Supplied

Sodden pastures could become a major feed issue for many lower North Island farmers even after the rain stops and growing conditions improve.

That's according to Manawatu agronomist Laura Akers, who says paddocks damaged by constant wet weather will not grow as much grass as normal during summer and autumn if they are not repaired.

"The good news is that there are recovery options available, however. The sooner farmers take stock of their situation and make a plan to restore paddocks affected by all the rain, the faster they will get back on track feed wise."

Damage has been widespread and unavoidable during the wettest season many farmers have ever experienced.

"In some cases it won't be possible to fix everything up straight away; the key will be to work out what can be repaired in the short term and what your feed needs are for the rest of the season so you can get organised and be ready to act as soon as conditions improve."

Laura says the main concern is filling the gaps left after pugging or treading damage before pastures become overrun with weeds and/or unproductive grasses like poa annua.

Remaining ryegrass will not fill those gaps, because ryegrass is not a spreading plant.

Repair options vary, depending on how badly each paddock has been damaged, so it's important to prioritise them according to their condition.

Where whole paddocks have been severely pugged, the best option is to consider full pasture renewal, either through a summer crop like 501 Chicory, or, in summer wet/irrigated areas, through grass to grass.

On farms with several distinct areas of damage, she encourages farmers to mark all of these areas on a farm map and get a contractor to come undersow them with Shogun hybrid ryegrass as soon as soil temperatures rise above 8 degrees C.

"Shogun has the real advantage of establishing quickly at cooler temperatures, because it is winter active. That combined with its high dry matter yield make it very valuable for undersowing in these conditions."

To fix small patches of damage, she recommends farmers oversow ryegrass and clover seed, to keep weeds at bay. Soil temperatures need to be above 10 degrees C for this to be successful.

Another potential issue caused by continual wet weather is that many farmers have not been able to graze paddocks down to correct residuals during spring, she says.

This will reduce future pasture quality and growth if it continues. "The best thing to do now is to try and make a conscious effort to get on top of this in the second grazing round, to set pastures up well for the rest of the season."

For more advice on getting pastures up and growing again after weeks of wet weather, visit www.agriseeds.co.nz or www.dairynz.co.nz