4 
Forsythia ovata, a native of the slopes of the Diamond Mountains of 
Korea, and in its range the most northern of the species of Forsythia. 
It is a large shrub with light yellow branches, broad, long-pointed, 
coarsely toothed leaves from 4-5 inches long, and from 3-4 inches wide, 
and clear primrose colored flowers rather smaller than those of For¬ 
sythia Fortunei or any of the forms of F. intermedia) they open about 
a week earlier than those of the other Forsythias. This Korean For¬ 
sythia promises to be a useful addition to early spring flowering shrubs 
and to be hardy in parts of this country where the other Forsythias 
cannot be successfully cultivated. The Arboretum plants were raised 
from seeds collected by Wilson in Korea in 1918. 
Other plants also in bloom are many Poplars and Willows. Erica 
carnea, the only species of the true Heaths which is entirely hardy in 
this climate has been covered during the last two weeks with its bright 
rose-red flowers. The bright yellow flowers of the Leatherwood {Dirca 
palustris) and the Spicebush {Benzoin aestivate) make these two widely 
distributed native shrubs attractive features of the Arboretum at the 
end of April. They are plants still too little known to gardeners. 
April Flowering Rhododendrons. The earliest of these, the Siberian 
R. dahuricnm, which can be seen on Azalea Path is now well covered 
with its small rose purple flowers. Last year they were fully open on 
April 12 and were ruined by frost on the 21st. They may be ruined 
again this year for it is not too late for killing frosts. The flowers of 
the north China Rhododendron mucronulatum which open usually two or 
three days later than those of the Siberian plant are less delicate and 
are rarely injured by frost. On the lower side of Azalea Path there 
is a mass of this beautiful plant which is well worth a place in the 
spring garden. The plants of the hybrid Rhododendron {R. ciiiatum x 
dahuricum) known in gardens as R. praecox “Early Gem” in the gen¬ 
eral Rhododendron collection are covered with expanding flower-buds. 
This is an interesting and handsome plant but the flowers are very del¬ 
icate and five years out of six are ruined by frost. 
Mr. J. G. Jack of the Arboretum staff will conduct a Field Class on 
Saturdays during the spring and eaaly summer, to assist those who 
wish to gain a more intimate knowledge of the native and foreign trees 
and shrubs which grow in New England. Instruction will be given in 
informal outdoor talks and in the examination of the plants. Different 
botanical groups will be visited at each meeting, although any trees 
or shrubs found may form subjects for study. No technical knowledge 
or special preparation is required in order to join the class as the in¬ 
struction is intended to be simple in character, affording opportunities 
for questions and answers relating to the specimens under observation. 
Unless otherwise notified the class will meet promptly at ten o’clock 
in the morning, on Saturdays, in the Arboretum at the Forest Hills 
entrance, beginning April 28th. The class will close on the 23rd of 
June. The fee for the course is $5.00, payable in advance. 
