Late Fall!
Tiny acorns yield massive trees in relatively short
time
Dear Janet,
I was glad you wrote, "Trees grow faster than people
think they do. Beeches, oaks, ginkgos and others are mistakenly
assumed to be slow growers, and so are sometimes overlooked as
potential shade trees." I planted acorns 30 years ago. The bur oaks
and white oaks that grew from them are massive trees now. It's
amazing how fast they grew, wonderful to see them now and know I
planted them.
M.G.,
Dear M.G.,
It's been said, "It's good to watch things grow, it gives you
faith in life." You're a great example of that, as is G.V.A.
who in his seventh decade is still planting new hickories, using
the sweetest nuts from the best trees on his property.
Who knows where the notion originated that majestic trees, most
desirable for those who want to plant a legacy, require many
generations to attain good size? Certainly the experts know
otherwise.
Professor Leon Snyder of the University of Minnesota, whose life
work revolved around plants for Great Lakes landscapes, wrote in
"Native Plants for Northern Gardens" that white oak is reported to
be slow growing but in good soil the growth is comparable to other
shade trees. Professor Michael Dirr, author of "Manual of Woody
Landscape Plants," a standard reference in universities and
nurseries all over North America and Europe, reports that red oaks
grow as fast as red maples at 2 feet per year and pin oaks grow
even faster, 12 to 15 feet over a 5 to 7 year period.
Given the right environment, a tree can even overcome slow
genes. A ginkgo tree, writes Dirr, is generally slow to medium at
10 to 15 feet over a 10 to 12 year period, but will grow very fast
with adequate water and fertilizer -- which explains one in my care
that has been rocketing along at 18 to 24 inches per year.
Similarly, while the English expect European beech to grow 18
inches per year, and I can, too, after watching my own 6 foot
tricolor beech reach 20 feet in eight years, Dirr reports it as
"much slower growing in the South."
Longevity may work against a tree's growth rating. Dirr reports
that even though we see a white oak put on 12 to 15 feet in a 10
year period, it slows down once it's 20 to 30 years old. So, M.G.,
your white oaks may have grown 50 feet in 30 years but will be only
100 feet tall after 200 years, an average growth rate of 6 inches
per year. Along that same line, Dirr writes that even if a gingko
attains a fast rate of 18 inch per year as a youth, it can be
considered slow if you count its growth over many years. He cites
one he admires in London's Kew Gardens, recorded as growing only 56
feet between 1762 and 1890.
Short reports
You missed some red fall color plants!
G.H. wrote to tell me I should have included trees such as
the Sargent crabapple in his yard, for red fall color. "It's not
the leaves, it's thousands of tiny red crabapples, which will stay
red and keep the tree colorful right through winter."
My previous article was devoted to fall leaf color, G.H., but I
agree persistent fruit is a great attraction in the winter
landscape. Alongside your tree we can list crabapples 'Molten Lava'
and 'Adams,' mountain ash (Sorbus aucuparia), Michigan
hollies (Ilex verticillata) and cranberry bush viburnum
(V. trilobum).
Green thumbs up
to speaking up.
Green thumbs down
to leaving garden soil bare and exposed over winter. Winter
rains pulverize soil particles and can undo all you did in a year
to attain loose, well drained soil. If you must follow that
ridiculous and destructive urge to remove every fallen leaf from a
property, topdress bare beds with mulch, compost or evergreen
boughs to absorb the impact of weather.
Originally published 11/22/03