The two entries of A/opecurus alpinus survived 
in the boreal garden at Palmer, but winter-killed 
at Prudhoe. The entries of Deschampsia 
caespitosa and Poa alpina winter-killed in both 
gardens. Not all of the Alaska entries thrived in 
both gardens. A hairgrass biotype from a south- 
central Alaska subalpine meadow winter-killed 
in both gardens. A southcentral coastal entry of 
Alopecurus experienced considerable injury at 
Prudhoe. Arctic entries of Arctagrostis latifolia 
had a difficult time at Palmer. 
As would be expected, production was 
generally greater at Palmer than at the Prudhoe 
site. Differences in production between the two 
sites were often greater for the boreal entries 
than the arctic entries. Greater dry weights at 
Palmer were due to more abundant tillering and, 
in most cases, flower culm production. The 
hairgrass entries, however, tended to converge in 
dry weight production at the two sites in the 
third year. 
Though dry matter production was generally 
greater at Palmer, leaves tended to grow longer 
and wider at Prudhoe. In some cases leaves were 
appreciably wider at the arctic site. This prob- 
ably can be attributed to longer photoperiods 
with lower evaporative stresses in the Arctic. 
The degree to which arctic limitations on 
growth also restrict the effective range of genetic 
105 
variability and plasticity of plants requires clari- 
fication. Mosquin (1966) and Savile (1972) pro- 
posed that members of the arctic flora are 
genetically uniform. Such constancy was 
thought to be an inevitable consequence of 
means adapted by plants to speed up seed 
production. Bocher (1963) observed, however, 
that ‘‘...all species are more or less 
variable...” 
In this study a great deal of variability was 
expressed in the number of flowering culms and 
amount of top growth produced. For example, 
shoot weights of arctic biotypes of Deschampsia 
caespitosa ranged from 40g to almost 90g at 
Palmer in 1973, and from 35g to 90g in 1974. 
Production at Prudhoe varied from 10g to 40g 
in 1973, but only from 35g to 43g in 1974. 
Variability in flowering culm production was 
even greater for these entries — from 3 to 106 at 
Palmer and 3 to 62 at Prudhoe in 1973, and 
from 43 to 95 at Palmer and 49 to 194 at 
Prudhoe in 1974. The boreal entries of hairgrass 
also varied a great deal in their performance at 
both sites, as did entries of other species. 
The study has provided some information on 
the phenotypic plasticity of northern ecotypes. 
Plasticity in metabolic reactions with tempera- 
ture has been demonstrated in arctic and alpine 
ecotypes of Oxyria digyna (Billings et al. 1971). 
ARCTAGROSTIS LATIFOLIA — SHOOT WEIGHTS 
EAGLE HATCHER 
ORIGIN: PRUDHOE PRUDHOE SUMMIT TOK JCT. TOK JCT. TOK JCT. EUREKA PASS 
(2n = 56) (2n = 28) (2n = 56) (2n = 28) (2n = 56) (2n = 42) (2n = 28) (2n = 28) 
55 Palmer Transplant Garden 
50 O---—-O Prudhoe Transplant Garden 
45 
40 
35 
2°30 
25 
20 
15 
ug -.) Pp 
5 Onn ah 
1972 73 74 72 73 74 72 73 74 72 73 74 72 73 74 72 73 74 
Fig. 12. Shoot weights of Arctagrostis latifolia over 2-year period. 
severely injured or winter-killed. 
YEARS 
4/ Entry 
