Plate XVIII. Figure 117.—Pleurotus ostreatus.
Two-thirds natural size.
Gills broad, decurrent, subdistant, branching at the base, white or whitish. The stem when present is very short, firm, lateral, sometimes rough with stiff hair, hairy at the base. Spores oblong, white, .0003 to .0004 inch long, .00016 inch broad.
This is one of our most abundant mushrooms, and the easiest for the beginner to identify. In Figures 116 and 117, you will see the plant growing in imbricated form apparently without any stem. In Figure 118 is a variety that has a pronounced stem, showing how the stems grow together at the base, the slight grooving on the stems, also the decurrent gills. In most of these plants the stems are plainly lateral, but a few will appear to be central. It will be difficult to distinguish it from the Sapid mushroom and for table purposes there is little need to separate them. In Ohio the Oyster mushroom is very common everywhere. I have seen trees sixty to seventy feet high simply loaded with this mushroom. If one will locate a few logs or stumps upon which the Oyster mushroom grows, he can find there an abundant supply (when conditions are right for fungus growth) during the entire season. It is almost universally a favorite among mushroom eaters, but it must be carefully and thoroughly cooked. It grows very large and frequently in great masses. I have often found specimens whose caps were eight to ten inches broad. It is found from May to December.
Figure 118.—Pleurotus ostreatus. One-half natural size, showing gills and stems.