VTree Update

Back in December, I learned that the Virginia Tech Department of Forest Resources and Environmental Conservation had released its tree identification app for Android. True to their word, the folks at VT DFREC then released the iPhone version in short order, appearing in the App Store in late January. Now anyone in North America with a smartphone can figure out which of 969 species he or she might be staring at.

The joy of this app is being able to use what the Dendrology at Virginia Tech website calls a "Multichotomous Key". In other words, one can choose among several choices that describe a given characteristic and may use any set of pertinent characteristics to build a query. This is opposed to the old, analog "Dichotomous Key" that sent you down a narrow branching path until you got stuck because the specimen you were looking at wasn't in flower, for example.

This is all great, but how good is their database? Can the app really help you identify your tree? I headed off to the woods to find out. With the trees ablaze in new spring foliage, I relied primarily on leaf characteristics. Frankly, this is what most people do. So running through the process with several species common to north Florida the results were as follows:

	Ulmus alata (Winged elm)	Diospyros virginiana (Persimmon)	Cercis canadensis (Redbud)
Growth Habit	Tree	Tree	Tree
Habitat	Mesic	Mesic	Mesic
Leaf Type	Broadleaf	Broadleaf	Broadleaf
Flower Color	Not sure	Not sure	Red/pink
Fruit Type	Not sure	Not sure	Not sure
Broadleaf Type	Simple	Simple	Simple
Lobes	No lobes	No lobes	No lobes
Edges	Serrate	Entire	Entire
Shape	Oval, widest below middle	Oval, widest below middle	Heart-shaped
Thickness	Thin	Thin	Thin
Broadleaf Arrangement	Alternate	Alternate	Alternate
Bundle Scars	Not sure	Not sure	Not sure
Leaf Scars	Not sure	Not sure	Not sure
End Buds	Not sure	Not sure	Not sure
Special Features	Corky growth	Not sure	Not sure
Identified?	Yes	Yes	Yes
Alternatives Offered	Celtis lavigata	48	0

	Quercus shumardii (Shumard oak)	Cephalanthus occidentalis (Buttonbush)
Growth Habit	Tree	Shrub
Habitat	Mesic	Flooded
Leaf Type	Broadleaf	Broadleaf
Flower Color	Not sure	Not sure
Fruit Type	Not sure	Not sure
Broadleaf Type	Simple	Simple
Lobes	Lobed	Not lobed
Edges	Toothed	Entire
Shape	Oval, widest above middle	Oval, widest below middle
Thickness	Thin	Thin
Broadleaf Arrangement	Alternate	Opposite
Bundle Scars	Not sure	Not sure
Leaf Scars	Not sure	Not sure
End Buds	Not sure	Not sure
Special Features	Not sure	Not sure
Identified?	Yes	No
Alternatives Offered	Nyssa sylvatica, Quercus michauxii	7

The app included the correct species in all but one of the test queries. Buttonbush is in their database as a possibility for my locale, but for some reason, the list of characteristics (all of which correctly describe the species) failed to offer it as a possibility. The list of possible species containing persimmon is much too long, but that means looking at a few of the characteristics I skipped. Accurately describing a tree's bark is very difficult in most cases, so it's not a surprise that they left it out of the interview process. However, adding bark as a characteristic could have nailed the identification of persimmon. The other three species would have been easily identifiable using this app.

Although there is room for improvement, this is still the best, most comprehensive tool of its kind that I've seen. For those with a real interest in trees, particularly if you find yourself in new territory, this app is sure to deliver a real education and a lot of fun.