Nhu: In the human digestive tract we use good guys to keep the bad guys at bay. It's known as competitive exclusion. Happy Holidays. Arnold New Jersey On 12/25/13, Nhu Nguyen wrote: Merry Christmas everyone! I finally have some time to try and catch up with posts on the forum. This response is a little late but I feel that its important to say a few things about the topic of mycorrhizal fungi, which is what I study. Mycorrhizal fungi are divided into two groups, the ectomycorrhizal fungi which associate with trees and arbuscular mycorrhizal fungi which associate with mostly herbs, grasses, and sometimes trees. Members of the pine family such as pine, spruce, fir, douglas fir are obligately dependent on ectomycorrhizal fungi and vice versa. However, it's hard to say that the white hyphal threads you observe underneath pine/alder trees are mycorrhizal. More often than not, they are saprobic fungi, and are only interested in breaking down the dead leaves. The observation that leaf mould with white hyphae protects bulbs is interesting and make good ecological sense. You're using one group of fungi to outcompete another group. In this case, using saprobic fungi to out-compete pathogenic fungi. The saprobic fungi will take over the growing medium and excludes pathogenic fungi from entering the arena, thus protecting the plants. For the most part, plant pathogens don't make visible hyphae because the hyphae will grow inside the plant and not in the substrate where they cannot compete well with saprobic fungi. Nhu On Sat, Dec 7, 2013 at 1:17 PM, Mark BROWN <email@example.com> wrote: > The bases of the stalks with some mycorhiza present was enough. > The white threads soon colonized the whole heap and gave quite a crop on > and off as a bonus. > I don't know what species I have in the leafmould though.