Before you read
through this booklet, it might be a good idea to get some feeling for
the terms I use in naming plants regarding their genus, species, etc.
Michael Dirr, in his marvelous book Manual of Woody Landscape Plants,
has on page 22 of the 1990 revision an excellent essay on nomenclature.
He is a professor of horticulture and does things correctly. Being a
nurseryman, I've sort of formulated my own way of doing things over
the past few years, and not being in academic circles, I figure I can
get away with it. I'm close to being correct, but not entirely so. Here's
an explanation to help you understand my method, using Acer palmatum
dissectum 'Ever Red' as an example.
Acer - I consider this the "genus" name - genus is
palmatum - I consider the "species" name - species
is Japanese Maple.
dissectum - I consider the "group" - the Threadleaf
Japanese Maple group.
'Ever Red' - I consider the "variety" name - variety
is 'Ever Red.'
"Varieties", to me, are plants that have to be propagated asexually
by either cuttings or grafts because they come from one original plant
or mutation on a plant. They will not come true from seed. For instance,
Pica glauca 'Ed Hirle' is a distinct variety that came from a mutated
branch on an Alberta Spruce. This branch mutation is called a "sport".
"Clone", to me, is a group of plants which comes from one original plant
or branch sport where all reproduction is done asexually. In my terminology
"clone" and "variety" are the same except that a variety has been given
a name - clones do not necessarily have to been given a name. For instance,
we are growing all our Enkianthus campanulatus 'Summer Hill' from cuttings
we took from a superior seedling many years ago. 'If we had just continued
to sell it as Enkianthus campanulatus, I would say, "We are selling
a very nice clone. - we grow them all from cuttings and not from seed".
However, since we put the name 'Summer Hill' on it, I now call it the
"variety" 'Summer Hill'.
When I mention the term "type" plant, I mean the plant as it would be
found in the wild. This, of course, opens up room for a lot of variation
since plants in the wild are produced from seed, and there are variations
in their growth due to genetic factors, the localities they come from,
soil they are growing in, etc. However, there are general similarities
within each species, and this is to what I refer.
I use the word "form" very often when I'm describing plants. It's a
nice word, I like it, and it can mean almost anything.