So far, however, we have been considering how to make the most of a stand of many ages, due to constant reproduction permitted by the light supply in a fairly open forest. On the other hand, yellow pine sometimes produces a mature stand so heavy that there is little young growth beneath it, or even a thin old stand with either little reproduction or an invasion of lodge-pole pine. Such conditions are usually due to fire at some period. In the first of these cases, usually the dense stand has resulted from a fire which destroyed its predecessor not so completely as to remove the seed supply, but sufficiently to afford light for a more uniformly dense crop of seedlings than would occur in the normal forest. These have been thinned out as the stand grew old, but never to a degree which allowed much reproduction beneath them. The natural cycle will be begun again in time, for toward the end of the life of this unusually heavy stand, seedlings will begin to appear gradually as individual old trees die and admit more and more light. The other exceptions described are due to more recent ground fires which have destroyed only the less hardy young growth and perhaps also encouraged the lodge pole which, within its range, is always quick to take burned ground. The same result is almost sure to follow the "Indian" method of forest protection sometimes advocated, which consists of purposely running ground fires frequently in order to prevent accumulation of sufficient debris to make an accidental fire fatal to timber of commercial size. While such immunity may be secured, and perhaps without sacrifice in stands so heavy as to have no reproduction or when the latter has already been destroyed, it is obviously at the expense of young growth if any exists. The counter argument that a small proportion escaping will be sufficient for the second crop is fallacious, because good timber will not be produced from these scattering seedlings subjected to strong light by later logging. Other means are necessary if the forest is to be reproduced. This brings us to the possible management of yellow pine as an even-aged forest. Thoughtful foresters are beginning to suspect that while the "Indian" system of fire protection will usually be fatal if ordinary logging practice is followed, it may serve as an adjunct to a system which, if carefully applied, will be better than selection cutting for some of our pine areas. This plan is suggested where there is little young growth worth protecting and consists of depending upon seed trees almost entirely for reproduction, protecting carefully until the resultant even-aged second growth is large enough to stand Blight fire, and then burning periodically at such a season and with such safeguards as will prevent the fire from being injuriously severe.