August 13, 2016
Are the seeds inside the "Prickly balls" that fall off the gumball trees, and can you plant the whole thing?
I like sweetgum trees, but most people run from them, versus wanting to plant them. The spiny fruit does contain seeds, in fact, quite a few. Each sweetgum ball has about 40 to 60 capsules, with each containing one or two seeds. Fertile seeds are black with wings on either side; infertile seeds are yellow and wingless. Harvest the sweetgum balls when they are fully brown, but before they dry out. Once they dry, they open and scatter the seeds. Harvest the sweetgum balls and let them dry out on sheet of paper. Then when the seeds start to fall out, collect them and put the fertile seeds inside a plastic bag filled with moist sterile potting soil. Put that in your refrigerator for three months and then plant the seeds in a pot outside. This cool, moist storage period in the refrigerator is known as stratification and is needed to break the seed dormancy. As an aside, researchers have discovered that the unripe fruit of the sweetgum tree contains a key ingredient used in Tamiflu called Shikimic acid. Interestingly enough in medicinal lore, Sweet Gum tea was an herbal treatment for the flu and the Cherokee made a tea out of the bark. They knew what the scientists are just now discovering.
In front of our house we have two 17'x17' plots of ground between sidewalks. We would like to plant a tree in each plot that would not eventually lift the sidewalks with their roots and would not get too tall. We have tried dogwoods, red buds, flowering cherry, but the full sun and heat got to them. Someone suggested Bradford pear, but my wife and I are allergic. Are there any other trees that we might plant that have a better chance of survival?
Definitely not a Bradford pear—they can get 40 feet tall and 40 feet wide—way too large for this location. You have several options. The new trend in trees is to produce fastigiated forms—those that grow with a narrow growth habit. Fastigiated sweetgum, fastigiated hornbeam, English oak, and Autumn Spire red maple are just some choices that would work. These would get tall, provide shade, but would fit the situation with a narrow canopy. Smaller trees to choose would include redbud (they usually take full sun well), crape myrtle, and fringe tree.
Sweetgum trees have beautiful fall color and a pleasing shape, but oh, the plague of the sweetgum balls. Here's my question/problem. Ten years ago I bought a ten foot sweetgum tree from a nursery and was told it would not produce the dreaded gum balls. It didn't for 8 years or if there were any, I sure didn't notice them. Last year, for the first time, I noticed a few. This year, the darn things are all over the tree. How can a sweetgum tree go from being "gum ball-less" to "gum ball-full?"
It has to be old enough to begin to bear fruit. Most sweetgum balls will begin to bear at on average, 8-10 years, and will continue to produce the rest of their lives. There is a fruitless variety that has rounded lobes instead of the pointy ones of the fruited variety. Fruitless varieties are typically grafted trees, and if they are killed beneath the graft union, the root stalk is typically a common sweetgum and will bear fruit. In a recent column we discussed the merits and lack thereof for sweetgum trees. Here isare some additional responses and questions from readers: I would suggest one other attribute of the sweet gum. In 1953, when I attended the Boy Scout Jamboree in California, I took several sweet gum balls to trade with other scouts for different items of equal value. I called these gum balls porcupine eggs to suggest that porcupines grew in the forests of Oklahoma and Arkansas. One scout from California traded me a block of California Redwood with inscription and a clear finish. We were both pleased with the trade. Since then, I have pointed out to many kids that I have encountered in the woods to be on the look out for porcupine eggs on the ground. I do have a certain degree of credibility since I have a degree in Forestry from Oklahoma State University. No telling how many kids are still looking for porcupines in our forests.
Someone told me last week that if you top a sweetgum tree it won't produce gumballs for 4 or 5 years. Is this true? I have a huge sweetgum tree in the backyard that my wife loves for the shade it produces, but I hate the gumballs I have to deal with all year long. I want to cut it down, but if topping it will stunt the gumballs, I'm willing to try that.
Not true, and very, very bad for the tree to be topped. Topping a tree leads to a hollow, unsafe tree so should never be done. Sweetgum balls can be a nuisance, but the fall color and the overall shade make it worthwhile. If you grow hostas, the sweetgum balls make a great mulch to keep slugs away, and if neighborhood cats use your garden as a litter box, sweetgum mulch keeps them away. I am still surprised that some enterprising gardener hasn’t bagged the stuff and sold it for either or both uses. Maybe you have a new cottage industry in your yard.
Could the thorny seeded tree you talked about Dec. 24 be a sweetgum instead of a chesnut? I don’t think there are any chesnut trees left in Arkansas. Without a picture, how can I be sure of the difference? What about a horse chesnut? I think they are poisonous
It certainly is a possibility that the thorny fruits were sweetgums. I had chestnuts on my mind, since someone sent me a sample and asked for identification recently. Chestnuts were practically wiped out in the United State due to chesnut blight, but they are not extinct, and there are millions of seedlings nationwide. We have been seeing a resurgence of the American chesnut tree in Arkansas. I have seen fruiting trees from Baxter County, to Petit Jean, Little Rock and Monticello. It’s fruit has lots of spines on the outside and a narrow, toothed leaf and edible inside nut. The American chesnut foundation is also breeding disease resistant varieties which should soon be available to the public. The sweetgum tree does have thorny smaller fruit, but you won't get too much inside, nor is it edible and it is very widespread in our state. The single leaves look almost like stars with five points. The horse chesnut is also called a buckeye and while it does have a large poisonous seed, the pods have small thorns, but it is not as common in our state as the red buckeye, which has . As with all members of the Aesculus (horsechestnut family) they have compound leaves with 5-7 leaflets. I have attached pictures of all three for proper identification.
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