UNIVERSITY OF WIEDNSIN                       , ., 
COLLEGE OF AGRICULTURE 
MADISON, WISCONSIN 
DKPARTMENT Or HI UNIULTURIK 
November 29, 1936 
Prof. Aldo Leopold 
Soils Building 
Dear Aldo: 
It is very imperative that we get as much of the original 
data from the arboretum as possible. We have spoken a number of times 
about the necessity of a comTlete plant survey of the area and that is 
as far as we have gotten. Ervery day we are losing valuable information.

What hi happened on the area the pat 4 years? There has been a de- 
cided change in the flora of the fields from annual weeds to perennial 
grasses. In some places shrubs and even trees are beginning to come in, 
but where is the actual data on this transition?  Things are also going 
on in the woods since they were taken over. Small trees and shrubs are 
coming back with the exclusion of the cattle and horses, but where are 
the exact records of what is going on? We should know beyond question 
what the area was like at the time we took it over. 
Lhery possible effort should also be made to get a complete 
detailed soil survey of the various areas as soon as possible. This 
should be re-done at least every five years to see what is happening. 
This is one of the most important long-time problems. le should know 
Just what effect the various plants have on the soil. 
The Soils Departient was going to make us a detailed survey 
with one of the soils classes. Maps etc. were furnished, but to my 
knowledge nothing has been done as yet. Do you hlink it would be ad- 
visable to go to the Dean with this 1roblem, or do you have something 
else to sug-est? Prof. Jamaes Dickson found out while in Waehington D.C.,

that fertilizer could be obtained for experimental *urposes free of charge,

freight I-epaid, from T.V.A. I think it is very important to tcke ad- 
vantage of this because a naber of our soils are in very poor condition.

It is esepcially imortant that we do all we can to improve the soils 
where we are trying to establish such advanced associations as hard mple

and hemlock. There are also some places on the proposed, prairie where 
additional fertilizer should give some good results. As I understand it,

phosphate and nitroeen fertilizers are available, but at present there is

no pota&. 
Very truly yours, 
cc. to A. F. c,.allistel                     Ex-ecutive retor 
2. M. Gilbert                       'University Arboretum 
N. C. Fassett 
. . caffrey 
Colonel Jackson