LIVING STUMPS OF TREES 



BY C. C. PEMBERTON 



WHEN a tree is cut down it ordinarily dies or 

 sends up sprouts from the stump or roots. Only 

 a few conifers can sprout from the stump. In 

 others the stumps usually die. In some species, however, 

 instances are found of stumps which do not sprout but, 

 nevertheless, do not die. On the contrary they retain 

 their vitality to a surprising extent and apparently with- 



DOUGLAS FIR 



An example of remote and indirect root graft and consequent healing 

 of stumps. A and B are healed stumps whose tap roots have grafted 

 with the underlying roots of a large, foliage possessing fir tree fifty 

 feet distant. D.D D. are the roots of the large tree spreading laterally 

 at a depth of two feet below the surface. C is another small fir stump 

 healed over, having only indirect union of roots. 



out the aid of foliage. There has been much controversy 

 as to the cause of this remarkable state of affairs. Some 

 aver that union of roots of the stumps with those of 

 adjacent standing trees accounts for the phenomenon. 

 Others contend that it is due solely to the reserve 

 material in the stump, and in support of their contention 

 point to instances of stumps apparently isolated and 

 remote from other trees which nevertheless can make 

 bulky formations of new annual rings. 



According to a letter recently appearing in the Victoria 

 Daily Colonist, Victoria, British Columbia, from Mr. A. 

 D. Webster, Inner Circle, Regents Park, London, Eng- 

 land, the healing over of these stumps had attracted 

 attention in England early in 1800, and Grigor, an 

 English botanist who died in 1848, had described them 

 in his "Agriculture." French reviewers of the book, 



HI 



however, expressed doubts on the subject, saying that 

 it was "as likely for a pump to draw water without a 

 piston as for a tree devoid of leaves and branches to con- 

 tinue to produce annual layers of woody matter." Grigor, 

 nevertheless, had been able to prove by "occular demon- 

 stration," the truth of his assertion, although no decision 

 was reached as to the cause. 



Professor Somerville, of Cambridge University, Eng- 

 land, has lately expressed the opinion that though the 

 phenomenon is usually attributed to the natural grafting 

 of roots of the stump with those of adjoining trees left 

 growing, the subject has not been sufficiently investi- 

 gated. He distinctly states that, in larch, a certain 

 amount of growth can take place in a stem that has 

 been served, and that if such a stem is laid in a cool moist 

 place, the cambium becomes active in the spring and 

 a ten per cent annual ring can be formed in the ensuing 

 season. 



The matter seems to have received consideration also 

 in Germany. In the Kew Bulletin (1917, Nos. 9 and 10, 



DOUGLAS FIR 



This is an example of a natural root graft between two Douglas fir 

 trees. To the left is portion of the trunk of the tree which retained 

 its foliage and to the right the stump. The center of the stump is 

 decayed, but the rim of live wood around the outer edge is plainly 

 to be seen. 



P- 33). Mr. W. Dallimore, in his instructive article, 

 "Natural grafting of branches and roots," referring to 

 these stumps, quotes Sorauer, Handbuch der Pflanzen- 

 krankheiten, Berlin, 3rd ed., 1919, vol. I, p. 774, to the 

 effect that while root union may often be the solution 

 of the enigma, there are stumps too remote for such a 

 possibilty which nevertheless show bulky over-growth. 

 In the latter case, he thinks reserve material is responsi- 



