Invasive roots in veg patch

Mervo Mark

Hi

Last autumn I dug a load of well rotted garden compost into my veg patch and then covered it with strawed horse manure and covered the lot with polythene over the winter. I recently removed the polythene and dug in the decomposing manure only to find an invasive root system spreading across the patch. The roots are dark red and vary in thickness up to 4mm. Does anyone have any idea what this is?

Many thanks

Mark

nutcutlet

Are there trees around Mark? Willow and alder will grow into mulches and probably a lot of others as well. ,

BobTheGardener

Are you sure they are roots and not fungal mycorrhiza?  Those are usually very weak though, except for honey fungus.