With harvest approaching, College of Agriculture, Food and Rural Enterprise (CAFRE) tillage specialists have highlighted the options available to cereal growers, where the effective management of straw is concerned.
Yes it can be baled. But straw can also be chopped and, subsequently, incorporated back into the soil.
Strong demand for straw from livestock farmers for bedding and dietary fibre in recent years has resulted in the majority of arable farms in Northern Ireland baling, rather than chopping, straw.
Management of straw
Straw sales provide additional income and can aid cash flow, post-harvest.
However, nutrients will be lost from the field with the removal of straw and there is a risk of compaction due to increased trafficking within the field during baling and loading.
Weather conditions, particularly if harvest is delayed, can also make saving straw difficult.
A CAFRE spokesperson stated: “Straw contains significant amounts of potash, and some phosphate and magnesium.
“Chopping and incorporating straw will ensure these nutrients are returned to the soil, thus improving soil health by adding organic matter and increasing carbon content of soils.
“Chopping also allows swift access for field operations such as establishing cover crops or early sown winter crops, although raking may be required to effectively spread chaff following combining.
“Short-term nutrient lock-up and the risk of carry-over of pest/disease can be issues with crop residues.”
Decisions on straw
According to CAFRE, there is an increased fuel cost associated with chopping straw and the ability to incorporate straw may be limited by the availability of combines equipped with straw chopping and effective spreading equipment on some farms.
“The decision to chop straw will be dependent on the value of straw at harvest time, the ability to chop straw on individual farms, and the perceived value of improving soil health,” the CAFRE spokesperson added.
“Where straw is removed and returned to the land as organic manure, nutrients are recycled, benefiting both arable and livestock enterprises.”
There is no straw incorporation measure on-offer to tillage farmers in Northern Ireland at the present time.
However, the issue was discussed at the recent farm walk hosted by Northern Ireland’s new Agriculture and Horticulture Development Board (AHDB) cereals and oilseeds monitor farmer, Alistair Craig.
National Trust farming advisor and former ADAS agronomist Kevin Duncan suggested that more should be done to identify ways of speeding up the decomposition of freshly incorporated straw within the soil.
To this end, he highlighted the work that had been carried out in England, assessing the impact of adding microbial supplements to newly planted cereal crops in the autumn time.
“This work be carried at the same time as fertiliser is first applied to newly established crops,” Duncan said.
All of the growers taking part in the farm walk agreed that adding organic matter to arable crops delivers the key benefit of feeding the soil’s biology.