THE SOUTHEEN" CYPEESS. 29 



pronged and multiple roots below the knee, it appears very probable 

 that the knees are developed not only for the purpose of increas- 

 ing the supply of oxygen which the roots are able to obtain di- 

 rectly from the water, but of enlarging and strengthening the basal 

 support. The evidence of this belief is (1) the general absence of 

 knees in swamp soils superficially dry during most of the year, (2) the 

 presence of knees where there is an excess of surface water for long 

 periods, (3) the rise of the knees approximately to the height of the 

 average flood level, and (4) the interwoven network of roots in the 

 superficial root system, and the anchorage afforded by the mass of 

 deep roots beneath the knees. 



REPRODUCTION. 



SEED AND GERMINATION. 



Cypress has the power of reproducing itself both by seed and by 

 sprouts from the stump. 



Cypress cones (" balls") contain from 18 to 30 twisted, sharply 

 keeled, or winged seeds 1 (PL XI). Large pockets or sacs in the 

 cone are filled with an exceedingly sticky, red, liquid resin, unpleas- 

 ant to the taste. This probably explains why the seeds are only in 

 slight degree taken as food by either birds or rodents. The outer 

 coating is thick and hard. When free from cone scales or other 

 materials there are about 5,000 seeds per pound. Upon ripening in 

 October and November, the seeds fall to the ground near the tree. 

 Unlike the seeds of most conifers, cypress seeds are not scattered to 

 any extent by wind and animals. Seed is borne in abundance. 

 Some is produced almost every year, and full seed crops, so far as is 

 known, occur at intervals of about every three years. Some of the 

 seed is aborted or infertile, so that germination averages usually 

 from 40 to 60 per cent. 



Tests 2 of seed collected in the two Carolinas in the fall of 1913 

 gave from 55 to 65 per cent of germination (Table 5 and PL XI). 

 The general average for seed from all sources is perhaps 40 to 50 per 

 cent. Seeds stored indoors in a warm, dry room from November 

 until the following April, 1913, gave 55 per cent germination, occur- 

 ring mostly in five weeks and reaching completion in seven weeks. 

 B of t be same lot after soaking in stagnant water in a warm room 

 for six weeks gave 65 per cent germination, complete in two weeks 

 from date of sowing, hi another test seed which was kept contin- 

 uou-l moi i and aerated under n :- r hiss jar for a period of four months 

 completed germination in seven days, 8 with a total of 87 per cent 

 germination. 



o Inch u Ide. 

 r In greenboo he Islington Experiment Station, U. B. Department 



Icultore. 1 be • eed w:j- collected at random from trees In North Carolina und South Carolina 50 to 

 md condition* for tl > practically ideal. 



> In June, 1913. 



