Pasture growth is a grazing resource and our main soil development tool. In the tree crops at this time of year we mow to set back the grass, and free up the soil and water resources for tree growth and fruiting.
Winter grazing only removes about 50% of the leaf area, with very little root growth retardation. The pasture recovers very quickly. The spring mowing removes almost 100% of the pasture leaf area, and substantially sets back the grass. Grass roots die, soil microbes decompose these, and tree roots and their fungal associates then explore those former grass root pathways for nutrients.
Early Spring this year saw cool weather, rain, a full soil profile of stored water, and surplus water in the upper profile.So we let the grass in the tree rows keep growing, using that surplus moisture, and adding more root material to the orchard soil.
Timing of the main Spring mowing depends mostly on water availability …. is the soil moisture better used for more grass growth, or saved for the trees?
Other factors we consider are
– availability of pasture for the goats, and of mown pasture for chicken forage
– very dense and vigorous grass growth competing with the trees…. size of trees vs the grass
– reducing fire risk for the coming summer, trying to allow time for surface mulch to begin to decompose
– use the tractor and fuel as little as possible while still maintaining good production and fire safety
– attraction and hosting of pollinators in the orchard other than honeybees, and insect predators for pest control services
– forage for honeybees, mainly the pollen resource for hive increase in Spring from capeweed daisy Arctotheca calendula
This very dense grass growth among smaller trees in the olive grove was probably beginning to compete with the trees.