Definition of a Tree
 

Somebody contended that tree is not a scientific term. However, Stearn's
Botanical Latin tells us that the Latin word for tree is arbor. He even
declines the word in several directions. It would be rather difficult for a
botanist to describe a new species if he had to say, "It has a single woody,
bark-covered stem, it is 30 feet tall at maturity, and it has branches near the
top," instead of, "It is a tree."
Beyond that, definitions vary. The Wordsworth Dictionary of Botany, 1996
edition, says:
A tall, woody, perennial plant, having a well-marked trunk with few or no
branches
persisting from the base.
The National Audubon Society Field Guide to North American Trees goes into more
detail. I dunno if it is peer reviewed or if you consider it scientific enough.
Their definition:
A tree is a woody plant with an erect perennial trunk at least 3 inches in
diameter at breast height, a definitely formed crown of foliage, and a (mature)
height of at least 13 feet.
I am also including the definition in the Wise Garden Encyclopedia, 1990
edition, although it is not a botanical book per se, just for comparison.
A tree is a woody plant with a single stem or trunk, usually without branches
to a height of 10 feet but crowned at the top with spreading branches, and
growing at least 20-25 feet. There are numerous exceptions...
Now put a chihuahua, a Boston terrier, and an Irish wolfhound together & define
Canis familiaris.
Iris,
Central NY, Zone 5a, Sunset Zone 40
"If we see light at the end of the tunnel, It's the light of the oncoming
train."
Robert Lowell (1917-1977)

Iris Cohen schreef
Somebody contended that tree is not a scientific term.

*********
Actually I said that "bonsai" is not a taxonomic term.
"Tree" must be one of the oldest scientific terms there is, easily preceding
"gravity" and "engine".
*******

However, Stearn's Botanical Latin tells us that the Latin word for tree is
arbor. He even declines the word in several directions. It would be rather
difficult for a botanist to describe a new species if he had to say, "It has
a single woody, bark-covered stem, it is 30 feet tall at maturity, and it
has branches near the top," instead of, "It is a tree."

******
Actually there are quite a few scientific terms to describe growth form (of
the mature plant), and they all have Latin equivalents.
********

Beyond that, definitions vary. The Wordsworth Dictionary of Botany, 1996
edition, says: A tall, woody, perennial plant, having a well-marked trunk
with few or no branches persisting from the base.

The National Audubon Society Field Guide to North American Trees goes into
more detail. I dunno if it is peer reviewed or if you consider it scientific
enough. Their definition: A tree is a woody plant with an erect perennial
trunk at least 3 inches in diameter at breast height, a definitely formed
crown of foliage, and a (mature) height of at least 13 feet.

I am also including the definition in the Wise Garden Encyclopedia, 1990
edition, although it is not a botanical book per se, just for comparison. A
tree is a woody plant with a single stem or trunk, usually without branches
to a height of 10 feet but crowned at the top with spreading branches, and
growing at least 20-25 feet. There are numerous exceptions...

Now put a chihuahua, a Boston terrier, and an Irish wolfhound together &
define Canis familiaris.

*****
If you put those three together you will likely have a dogfight?
PvR

There are numerous exceptions...

No, there is a continuum:

perennial herbshrubtree.

All possible intergradations occur.

There is no definite line where an herb becomes a shrub becomes a tree.

In article , IntarsiaCo
writes
There are numerous exceptions...

No, there is a continuum:

perennial herbshrubtree.

All possible intergradations occur.

There is no definite line where an herb becomes a shrub becomes a tree.


It's more unclear than you suggest - it's not a total ordering on a line
with unclear boundary points, but a more complicated topology. The
distinction between shrub and tree is made on several counts, which
means that there's several different ambiguous cases.

In the case of Lavatera arborea (Malva dendromorpha), is it a biennial,
a perennial, a subshrub, a shrub or a tree?

For a Victorian botanist's view on the general issue see

http://www.malvaceae.info/Literature...B/Chap1-1.html
(paragraph 13)
--
Stewart Robert Hinsley