The =Leaf-shedding Fungus= or =Pine-leaf Scurf= (_Lophodermium pinastre_) is a well-known and widely distributed species, and is usually found on the Scotch and Austrian Pines. The leaves, when attacked, wither suddenly and fall off, the fungus being most prevalent after unusually dry weather, or in early spring succeeded by a frosty winter. It occurs both as a saprophyte on dead pine leaves and a parasite on the living foliage. We have been most successful in combating the attacks and preventing the spread of the pest by spraying the affected parts with “Bordeaux mixture.” Young trees under ten years of age are most commonly attacked, and when this occurs in the nursery borders, the plants should be rooted out and burned. On several Scottish and English estates, thousands of Scotch Pines have been killed out by the attacks of the leaf-shedding fungus. One of the commonest fungi on old stumps is =Agaricus melleus=. It has no particular host, being found alike on coniferous and hard-wooded trees, and on both root and stem. Known as the honey fungus, and edible, this toadstool is about three inches in diameter, and of a yellowish-brown or rusty colour. It spreads with great rapidity both in the soil and between the bark and wood of the affected tree. The only remedy is digging out and destroying the fungus, and, in the case of healthy young trees, collecting and burning the mycelium. Next to the larch canker, one of the most destructive diseases of forest trees is caused by attacks of the =Bladder-rust= or =Cluster-cup= (_Peridermium piniacicola_). It is a wound fungus and attacks almost every species of pine, the Scotch in particular, especially when the trees are growing on light, poor soils. Young trees up to, say, twenty years old are most commonly attacked by this fungus, which appears like blisters, emitting bright reddish-coloured spores. Rooting up and burning all affected trees is the best remedy. [Illustration: POLYPORUS SULPHUREUS (ON WHITE POPLAR)] _Polyporus sulphureus_ attacks many species of trees—yew, poplar, etc. CHAPTER XXIII BARKING OAK Previous to the war the price of oak bark—about £2 10_s._ per ton—rendered it questionable whether from a purely financial point of view the operations of stripping and harvesting should be undertaken. Now, however, with bark at fully three times that figure, the operation is to be recommended.