78 
SKETCH OF THE CRATAEGUS PROBLEM, WITH 
SPECIAL REFERENCE TO WORK IN THE SOUTH.* 
My first critical work on the genus was begun in Vermont, 
June, 1899. Dr. Brainerd and I searched western Vermont thor- 
oughly, supplying Dr. C. S. Sargent with our material. I made 
several trips to Montreal, one to Riviére du Loup, Quebec, and 
another to the Berkshire Hills, Massachusetts. In the summer 
of 1903, two long trips were made in Vermont, for the Arnold 
Arboretum. 
In 1904, upon coming to the Garden, I commenced a special 
study of the group. 
The first thing necessary was the collection of a Crataegus her- 
barium. This has gradually been accomplished, and to-day we 
have what I consider the best Crataegus herbarium in the world. 
imens from the type trees. Nearly all of them responded and 
thus we have secured material that has helped to settle many 
problems. Later, in the spring of 1907, I sent out a circular of 
instructions for collecting Crataegi; this was sent mostly to bot- 
anists in the South and West and has secured more desirable 
specimens, which are still coming in, Since then I have paid 
special attention to material from parts of the country from which 
no collecting had been done. 
Second, my own collections have added largely to the herba- 
rium. In the fall of 1904 I spent five weeks in the field visiting 
many places in Vermont, several localities in Connecticut, the 
Berkshire Hills and the Arnold Arboretum in Massachusetts, 
and a number of localities in eastern Pennsylvania. In 1905 my 
collecting was done from New York City north to Dutchess 
ounty, New York. Since then trips have been made to the Ar- 
nold Arboretum and several extensive ones in the south. 
Third, our herbarium has been much increased by a complete 
set from the Biltmore Herbarium. Mr. Beadle sent collectors 
~ “* This paper was read at the aes conference of the scientific staff and students 
of the Garden, on February 2, 1910. 
