NATIVE 
HAWTHORNS 
FOR OUR GARDENS 
JOHN DUNBAR 
Assistant Superintendent of Parks, Rochester, N. Y. 
Clarifying Some of the Mysteries of the 
Strange Groups of Plants, the Latent Beauties 
of Which Have Only Recently Been Disclosed 
The fruits, like miniature ap- 
ples, golden, yellow, scarlet, 
and often persisting long into 
the winter, have attractive 
values for the landscape 
(Crataegus Barryana, 
crimson fruits, October to 
December) 
Editor’s Note: It is only with in the last Jew 
years that light has been shed on this wonderful 
family of small trees — perhaps the most conspicu- 
ous in fruit and flower and most widely distributed 
of all our native flora. The Park Department of 
Rochester, N. Y., has rendered American Horticul- 
ture many services, but in none of its unselfish 
work has it accomplished more than in lending 
its aid toward making these Hawthorns of ours 
better known to the public. In an earlier contri- 
bution to these pages (Garden Magazine for 
December 1912) Mr. Dunbar discussed the horti- 
cultural values of a selected list of species, which 
this present article amplifies. 
A f LTHOUGH they have always been conspicuous among 
C/ yg the native trees of our countryside, it is only just now 
j /Wm that the importance, usefulness and beauty of the 
North American Hawthorns is beginning to make an 
impression on some American landscape gardeners in the decor- 
ation of gardens, private estates, and parks. This present 
realization of their worth is mainly due to the vast and com- 
prehensive work accomplished by the Arnold Arboretum of 
Harvard University, under the direction of Dr. C. S. Sargent, 
in the demonstration of the adaptability of numerous species of 
American Hawthorns for the adornment of parks and gardens. 
The beauty of many of these native trees with their flowers in 
spring; ample foliage in summer; showy fruits of scarlet, crim- 
son, orange-red, and orange-yellow ripening in August or later, 
according to species, and maintained throughout the autumn 
until early winter, distinguishes them from all other small trees 
in ornamental plantations. 
Twenty-five years ago, fourteen species and a few varieties 
of North American Hawthorns were recognized. At the 
present time one thousand and twenty-one new species are 
known, and of that number five hundred and eighty-five species 
have been described by Doctor Sargent. The old conception of 
the species of North American Hawthorns and their limitations, 
was mainly adopted by Torrey and Gray in their “Flora of North 
America’’ in 1838. Four species were subsequently added by 
Engelman, Chapman, and Green. It has therefore been cus- 
tomary for many botanists to think of American Hawthorns 
in the terms of Torrey and Gray, and the scientific conclusions 
of some botanists in late years in multiplying species of Cratae- 
gus have been viewed with disfavor, and even with ridicule, by a 
few botanists. 
The modern conception of American Hawthorns began to 
reveal itself about 1898 at the Arnold Arboretum when a num- 
ber of young plants, that had been raised from seeds collected 
in different parts of this country eighteen or twenty years 
previously, began to flower and fruit. It was then seen that 
different plants (which it had been supposed belonged to one 
species) differed in their time of flowering, in the number of 
stamens and color of anthers, in the time of ripening their fruits, 
and in the form of the nutlets; and that these features were 
constant and could be depended on as distinguishing character- 
istics. And further, it was found that these seedling plants 
did not differ in any of these characteristics from the parent 
individuals from which the seeds had been gathered. 
The horticultural importance of this work developed with the 
scientific interest. From 1900 until 1917 four thousand ninety- 
five lots of seeds were sowed at the Arboretum. The collecting 
of these seeds from individual parent plants (all of which were 
carefully numbered, and which were represented by sheets of 
dried leaves, flowers and fruits in the herbarium, to which 
copious field notes on the type plants were added); the prepara- 
tion of the seeds for sowing; the observation of the germination, 
which does not occur before two years in the seeds of Crataegus; 
the transplanting the seedlings into nursery rows, until large 
enough to plant out permanently; all this detail and the extreme 
care maintained during all this time to preserve exact records, 
was indeed a tremendous task. It has been estimated that 
over 225,000 Crataegus seedlings were raised at the Arboretum 
during this period. 
Farge experimental sowings of cereal and forage plants have 
been made in different agricultural establishments in different 
countries, notably by the Vilmorins in France; but probably no 
institution, outside of the Arnold Arboretum, has ever made 
such extensive experimental sowings of any woody plants with 
such correct scientific details, and it is quite remarkable that 
this work was accomplished simultaneously with Mr. Wilson’s 
Chinese expeditions, which themselves weighed heavily on 
the facilities of the institution, as may be imagined. 
RATAEGUS species fall into twenty-one natural groups 
which can be recognized at a glance. 'For instance the 
Crus-galli group (which now contains 103 species) is based on 
a form to which Finnaeus gave the name. All are characterized 
by obovate leaves, wedge-shaped at the base, dark green above, 
usually serrate above the middle, leathery, with short petioles; 
fruit mostly subglobose to short oblong, with one to five nutlets 
prominently ridged on the back. The corymbs are many 
flowered. 
The origin of these species is difficult to explain. They pre- 
sent no evidence of hybrid origin as all the forms come freely 
102 
