I am involved in a landscaping project that borders on an apple orchard. We have been using bark mulch (from a local landscaping company) in the design. Is it possible that we could be introducing a new pest(s) or disease(s) into the apple orchard if the shreded bark mulch is distributed around or near the tree trunks? Thanks in advance for any help on this subject.
Compost the bark first, that should kill off any pests or diseases (which could be present if it was bark from apple trees that the company had removed). Spread the mulch in a thin (5-10cm) but wide layer, not in 'volcanoes' round the base of each tree
Anything is possible,you don't know the quality and condition of material used to make the mulch but I would expect that soil borne pathogens would have trouble migrating to the orchard. Is the orchard owner concerned about something in particular? Does your project really need bark mulch? Would composted mushroom manure work?
Composting the bark into a fine texture would diminish its value as a mulch, to a large extent it's the coarse texture of mulching material that makes it function as a mulch.
Mulch has many purposes including use as a soil amendment and as weed deterrant. Bark mulch as it robs the soil of nitrogen during the decomposition process which reduces it's value as a soil amendment which is why I use composted mushroom manure. Some weeds such as horsetail seems to thrive in that zone between bark mulch and soil. And, I think that some bark mulch, depending on the source, can have an unusual colour which I find districts from the plants and the overall composition.
Hey, I read your post and I do know from experience that the only thing I have ever noticed with Bark mulch is that it attracts ants....many ants. The black ones. And they do grow very large when they make Bark mulch their home. This is experience from living in the lower mainland in B.C. I don't know where your from. Drew.
Carpenter ants, presumably attracted because it is fresh wood. Wonder how far they get with trying to set up colonies in what turns out not to be a log or house wall.
It may be a late for this year but the problem can be minimized by exposing the mulch to high heat. One way is to spread it on a plastic sheet in a suny location and then cover it with a trasparent plastic sheet with some air trapped. Give it a good heat soak on hot suny days. It should minimize the problem. I have read that this method is used in place of crop rotation if rotation of crop is a problem for some reason. In this case the vege field is covered with transparent plastic sheets for a few hot suny days before planting crops.
http://www.puyallup.wsu.edu/~Linda ...ral Myths_files/Myths/Wood chip pathogens.pdf http://www.puyallup.wsu.edu/~Linda Chalker-Scott/Horticultural Myths_files/Myths/Bark mulch.pdf
