Vegetative Reproduction- Beech sprouts well from the stumps of young trees, but this ability diminishes after trees reach 10 cm (4 in) in d.b.h. Sprouts from stumps 25 cm to 38 cm (10 to 15 in) in diameter usually are short lived and do not attain tree stature. Numerous sprouts may develop on the trunk of beech immediately below a wound, and from the tops of stumps; here adventitious buds develop in callus tissue of the cambial region.
Beech trees may develop large numbers of root sprouts or suckers. Studies (30) have shown that reproduction is almost exclusively by suckering in the "beech gaps" and is abundant in the Adirondack Mountains of New York, in Maine (13), and in many other areas, often those near the northern and western limits of its range (11,42) where environments are severe (27). Suckering is stimulated only slightly by removal of the stem (18). Injury to roots appears to be necessary for the initiation of root sprouts in beech (19). Root sprouts arise from adventitious buds that form within callus tissues associated with wounds. Experimental injuries to roots in November resulted in fewer sprouts than did injuries inflicted in spring (20). Sometimes root sprouts develop where no apparent injury has occurred (39). There were relatively more root sprouts on southerly slopes in areas where freeze-thaw action tended to injure shallow or exposed roots and stimulate sprout formation, and where late spring frosts tended to injure or kill young seedlings. In Ohio, seedling regeneration was positively associated with northerly exposures and root sprout regeneration with southerly exposures (11).
In an undisturbed stand of mature beech in the Adirondacks, 1,730 to 2,220 root sprouts per hectare (700 to 900/acre; 7 to 12/tree) were counted (39). Casual observations elsewhere indicate that the number per tree may greatly exceed this figure.
Root sprouts can develop into desirable trees. Isozyme genetic studies have shown that some groups of overstory beech trees with similar phenotypic traits are clones (14). Sometimes root sprouts are ephemeral. In one reproduction study, made after a 60-year-old stand of beech was cut, all of the root sprouts died within 4 years. On the other hand, the trees in a 40-year-old beech stand of sprout origin averaged 10 cm (4 in) in d.b.h. and 11.6 in (38 ft) in height.
Beech limbs root in a single year when layered. Interspecific root grafting is common.