Magical Keys to the Kingdom of Plants
by Richard Brownscombe
Can we make a user-friendly key for stoppers based on Wunderlin and Hanen’s Guide to the Vascular Plants of Florida? Stoppers are the those much acclaimed landscape shrubs, sometimes recommended to replace the problematic exotic Ficus bejamina hedge. The native stoppers have many uses in landscaping and each is a bit different from the other. Many people are confused by them.
For those unfamiliar with a key, each number presents you with a choice. You select the description that best describes your plant. It either names the species or sends you to the next level with another choice. Continue through the levels until it names the species. Don't worry; we have an example below.
Our five South Florida native stoppers all belong to the family of plants called Myrtaceae, the Myrtle Family. According to Wikipedia, it is a big family that includes the myrtle, the bay rum tree, clove, guava, allspice, and eucalyptus. This key is just for the South Florida native stoppers.
A key to Five South Florida STOPPERS
All five native stoppers have a few characteristics in common:
a) two leaves are opposite one another on the stem,
b) sepals (the sheath-flaps covering a new bud) are open in bud,
c) flower petals are white; and the fruit is fleshy with just a few seeds.
Most of us, however, will notice that stopper flowers are a burst of white stamen like little star-burst fireworks and most stoppers are noticeably fragrant in bloom. Go to 1. for your first choice.
Note: If you have no flowers, there is a list below to help you look at the differences in stopper leaves. Leaf identification is much less certain, more difficult, so if you can find plants in flower, or wait until they do flower, identification will be easier.
Look at BOTH choices at each level (two 1's, two 2's, two 3's, etc).
1. Flowers on branched stalks with the central flower blooming first. Leaves may be a bit “puffy-looking”, that is, curled at the margins with a finely textured surface. The texture or rounded spots are easy to see with a hand lens. Leaves tend toward an elliptical shape, often with leaf tip and base more rounded than sharp. Myrcianthes fragrans, Simpson’s Stopper or Twinberry. The flowers smell great. The leaves have a eucalyptus-like fragrance. On large plants the bark may be reddish and peeling. The berries are bright orange-red. The flowers of the genus, Myrcianthes, are on branched stalks forming an “umbrella” (especially when there are a lot of flowers in a group) and the central flower blooms first. Simpson's Stopper doesn't have a lot of flowers on the branched stalk, but it still demonstrates the rule with the center flower blooming first.
1. Flowers on single (unbranched) stalks attached to the stem (inflorescence). Genus: Eugenia. The flowers of this genus tend to grow along the stem on short or long stalks and in clumps or bouquets. Go to 2.
2. Flowers very close to the stem on short (~1/4”) stalks. Go to 3.
3. Leaves typically oblanceolate or rarely elliptic (see shapes below), leaf tips NOT (usually) pointed. Eugenia foetida, Spanish Stopper or Boxleaf Stopper. Flowers are clustered along the stems, sometimes profuse and very fragrant. Fruits ripen from red to black. Leaves are often rounded at the tip end.
3. Leaves typically ovate or lanceolate or rarely elliptic (see shapes below), leaf tips pointed. Eugenia axillaris, White Stopper. Although crushed leaves don’t seem to have much smell, the air around a White Stopper has a mild skunky smell people may like or dislike. Flowers pleasantly fragrant. Leaves tend to be shiny, unlike the Red Stopper with leaves that tend to be dull.
2. Flowers on long, slender stalks well away (more than 1/4”) from the stem they are attached to. Go to 4.
4. Mature leaves are dull with a blunt* drip tip. Eugenia rhombea, Red Stopper. New growth may be red; flowers are fragrant; fruits are black when mature.
4. Mature leaves are shiny with a slender* drip tip. Eugenia confusa, Redberry Stopper. Red berries, of course, and new growth may be red; flowers are fragrant. This species is less commonly seen, than the Red Stopper above.
*Note: This difference in the drip tip is not easy to describe or see. It only describes the tip itself, not the whole leaf shape. The leaf surface (dull or shiny) is a much easier to see. This drip tip (once you become familiar with it) may be useful, however, to help distinguish the shiny leaf Redberry Stopper from the shiny leaf White Stopper when there are no flowers to compare. Redberry Stopper has longer flower stalks than White Stopper, if you can compare the flowers.
Stopper Leaf-only Identification
(when you can't compare flowers)
Remember, leaves are variable on most individual plants, so you are looking for a trend or “more-so-than-not” or a tendency among leaves. Until you become experienced, you are training your observation skills to look at the leaf surface, its general shape, and the tips of leaves. Crushing and smelling the leaf, putting a few in your pocket to compare with other plants, looking at and touching known stoppers will all help you learn and finally decide.
Start at the top of this list and work down because the process of elimination is helpful. The last species is also the least common, so you may find your answer before getting to the bottom.
Leaf is finely textured (read the Simpson Stopper description above). The crushed leaf has a eucalyptus-like (some say nutmeg) fragrance. Myrcianthes fragrans, Simpson’s Stopper or Twinberry
Leaf surface is dull and drip tip blunted. Leaves tend toward a prominent drip tip but sort of blunted. With a little experience this "blunted" drip tip (and dull leaf) will seem quite characteristic and unique to this species. Eugenia rhombea, Red Stopper
Leaf tips tend to be rounded, not pointed. Leaf is dull or shiny, but not "finely textured" like the Simpson Stopper above. Eugenia foetida, Spanish Stopper or Boxleaf Stopper
Leaf is shiny, but not textured and the tip is not round. There is a slight skunky odor in the vicinity. Leaf tends to be shiny with a variety of not-rounded leaf tips (blunted, pointed, or slightly drip tip). Eugenia axillaris, White Stopper
Leaf is shiny AND the drip tip is obvious on most leaves. Eugenia confusa, Redberry Stopper
Don't let leaf shape drive you nuts; it is hard. That's why seeing the flowers and using the key above is recommended. Like all skills, experience and being "fooled" by a particular plant will help improve your stopper identification skills. One day you may be one of the few who can identify stoppers by looking at their leaves.
Send me an email to let me know what works for you. When we get a user-friendly key, we will publish it on the Coontie website to help others untangle the stoppers.