First, the oyster mushroom is quick to spoil and so is presentable to the market for only a few days. Secondly, the spore load generated within the growing room can become a potential health hazard to workers thus pickers can become allergic to the spore. Sporeless strains, which tend to have short gills and are thicker fleshed, prolonging storage, are highly sought after by oyster mushroom growers. Thirdly, the growers must wage a constant battle against the intrusion of mushroom flies. Oyster mushroom attracts Sciarid and Phorid flies to a far greater degree than any other group of mushrooms.