R. E. HODGSON, Superintendent, Southeast Experiment Station, University of Minnesota.
When hiking with a Boy Scout troop, they often asked me, "What tree is that?" In summer I could usually tell an oak from a box elder but had never had much reason to go further into the subject until the boys exposed my ignorance. In self defense I began to hunt up the names and found it a most interesting hobby.
The University of Minnesota has a branch experiment station some 80 miles south of the Twin Cities and it is here that a few acres have been roped off as a testing site for whatever trees of interest we can persuade to grow. My job is with field crops and livestock but my golf, fishing, hunting and bridge are mostly played with a spade and pruning shears or wandering around in the brush somewhere looking for something new. Our soil is a heavy clay loam of Clarion type containing plenty of lime but often poorly drained. It is very rich and productive being at one time part of Minnesota's big woods. Native trees are basswood, oak, elm, ash, walnut and their associates.
My ignorance concerning trees is still profound and becomes more apparent as acquaintance matures, but it has been a lot of fun to start about 130 varieties of trees and shrubs and watch their development. The Latin names are mostly a mystery to me, but their habits, methods and rate of growth along with soil preferences and winter survival have furnished more entertainment for me than picking shot out of a dead bird or furrowing the turf on a putting green. It has been a real thrill to see cypress, sycamore and even a few yellow poplars, survive our rugged winters.
The project began with an attempt to collect native trees and expanded to make room for some exotics, just to see what would happen to them. Detours and by-paths included attempts to grow various conifers from seed and persuade cuttings to root. Somewhere along the line nut trees began to enter the picture and now these have an alcove all to themselves. Perhaps it started when a neighbor offered me $5.00 if I could tell whether a young sprout in his yard was butternut or walnut. He died before I found the answer which was probably common knowledge to most people. The color of the pith did not seem reliable, but at last a book pointed out the little moustache a butternut wears just above each leaf scar. It worked, and the thrill was equal to catching a 10 pound wall eye!
I was raised on the prairie part of southwestern Minnesota and it was a delightful surprise when I moved 140 miles east to find that one could gather almost any desired quantity of black walnuts from remnants of the old forest. After a few years these trips to the woods became less glamourous and the pickeruppers more critical. Many of the wild nuts were small and hard to crack. Perhaps a friend's Thomas tree in full bearing with its heavy crop of huge, tasty nuts inspired a wish to grow bigger and better producing trees near at home.
It looked easy to transplant vigorous, 6 foot black walnut whips which could be had for the digging. It took 10 years to learn that nuts properly planted would make larger trees in a decade than transplants. Digging 2 deep holes to move one tree seemed a waste of labor when one planted nut would better serve the purpose. Of course nut planting led to a contest of wits with the squirrels.
It was a funny sight to watch a helper carefully placing nuts at regular intervals in an open furrow and a big fox squirrel following 10 feet behind him, removing the prizes as fast as he could scamper up and down a nearby hollow oak. Our ideas concerning appropriate locations for walnut trees did not coincide with those of Mr. Bushytail. We learned that the simple way to plant walnuts in the woods was to pile a half a bushel here and there. The tree climbers took their toll, but did a good job of planting. Survival seemed better than when we placed individual nuts and "stepped them in."
The desire for bigger, better and more useful nuts led to the planting of a couple of acres to seed from various trees of known value. These will not come true of course but it is hoped that some day they may serve as material for a small nut breeding project in which an attempt will be made to combine some of the more desirable chromosomes into a single tree that retains the best of what we have in present selections, and adds a little more hardiness between growing seasons. Who can tell? We might find a tree that the walnut worms didn't like!
The squirrels didn't fancy our plans to grow trees in rows according to parentage, so they tried to improve our technique. We almost called in the F. B. I. to circumvent their machinations. Jamming an open tin can over the planted nut seemed to help. When the sprout came up we turned up the edges of the split can bottom just enough to let the tree through, but the sharp jagged edges seemed to discourage marauders. A lot of other methods were also tried.
From the Wisconsin Horticultural Society we obtained a pound of English or Persian walnuts in 1937. So far we have some 23 seedlings struggling to keep alive. They range in height from 18 inches to 7 feet and are definitely out of their range. Some years they grow 4 feet of new wood and some winters it all kills back. There seem to be differences in hardiness and—who can tell?—they might even bear a nut some day. Bark injury, which may be winter sun scald, has damaged some of the trees. One tree of the Broadview selection is alive after four years and may make a go of it.
Hickories grow wild in certain parts of Minnesota, but this doesn't happen to be one of those parts. They seem to do best where soil is acid in reaction and here we are amply supplied with lime. That may account for the slow growth of a grafted Hales hickory tree. It was 3 years old when set out in 1921. For the first 9 years it had just 2 leaves per year. Now approaching 30, the tree is 7 to 8 feet high and going up at the rate of 8 to 12 inches a year.
Nuts from Wisconsin, Michigan, and Minnesota wild hickories, have done better. At 8 years the trees are from 1 to 2 feet high, with a couple of Shakespeares, (geniuses) towering a foot above them. This may not be hickory country, but, by gum, they're growing! A couple of years ago, Dr. Brierley from the Central Station, Division of Horticulture, who has nut propagation as one of his minor projects, gave us 7 seedlings of shellbark hickory, (Carya laciniosa), from a tree planted many years ago by Peter Gideon of Wealthy apple fame. After 2 winters, these 7 seedlings are still with us and seem to grow faster than the shagbarks (ovata).
Other attempts to vary our diet (if we live long enough) are a few Chinese chestnut seedlings. A couple secured from the Nut Tree Nurseries, Downington, Pa., in 1940 are now 3 and 4 feet high and apparently in a good state of health. They are leisurely growing, which may be a good thing. Trees like the Manchurian walnut which grow 6 to 8 feet of new wood in a year, seem to freeze back and start over more frequently than the trees which poke along but harden their wood before cold weather. In 1946, a few more seedlings from D. C. Snyder, Center Point, Iowa, were set out and most of them have survived the first winter. Carl Weschcke reports that chestnuts do best for him at River Falls, Wisconsin, in sandy soil with an acid reaction. If I ever raise a chestnut, I'd like to send him one.
Fooling with nuts has led to another activity which has been pleasant though not very practical so far. Each spring, Dr. Brierley spends a couple of days with me trying to graft some of the named varieties to our available wild trees. We have raised nuts on some of the hickory scions grafted to the plentiful native bitternuts, but in general our grafts have failed. We have had good advice from many sources and have tried most everything but our successes have not been numerous enough to cause any inflation of the ego. We're inclined to think that the sudden wide variations of temperature which are common here in May, can be the controlling factor. We've made a few walnuts, hickories, and hicans grow, but still have too many zeroes for any complacency. This year may be our bonanza. Most of the grafts on some 40 trees are shooting buds. Perhaps it's the grafting tape we tried this spring. In 1948 we'll be able to write it all down in the book—and try again.
Nuts are not the only food crops growing on trees. We have read the glowing reports of sweet pods of honey locust grown on such varieties as Millwood and Calhoun, as told by John Hershey and J. Russell Smith. Our Millwoods all killed the second winter and this year we're trying Calhoun. Meanwhile, we're hunting for a hardy, northern grown sweet tree. Miss Jones asked nut growers to tell me what they had and several interesting replies and samples were received. The quality of the pods varied all the way from the sweet Millwood to our native honey locusts, most of which are so bitter and astringent that they remind us of a combination of green persimmons and red pepper. No sensible animal will touch them. Cions were received from a tree in Omaha, Nebraska, through the courtesy of F. J. Adams. These were grafted on local trees this spring and perhaps they will answer all of our needs.
Our attempts to grow better nuts in southern Minnesota have not caused even a ripple in the local economic situation, but it has been a lot of fun. Perhaps the greatest return so far is the interesting correspondence with like minded people in many localities. Amos Workman of Hurricane, Utah, sent seed of his best black and Persian walnuts, pecans and figs. The figs didn't even start (probably my ignorance), but we have trees coming from all the rest. J. Russell Smith has been most helpful with suggestions and the "Minnesota Horse Thief" as he calls me, has enjoyed his letters immensely. John Hershey has passed along some of his enthusiasm for trees and many others have contributed to the pleasure of a fascinating hobby.
It's fun to grow trees even though some of the unusual things provide only exercise and entertainment. Our persimmons grew from seed, were transplanted and came through the first winter! One pawpaw is still trying to get ahead of the winter set-backs, and a Macedonian white pine (said to produce edible nuts) is doing fine. Perhaps I'm the biggest nut of all, but I'm happy about it!