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- Creating a Glossary. 2.

Adventures with Epigeal and Hypogeal

In essence, epigeal and hypogeal are just arcane words for "above ground" and "below ground," respectively. I am only concerned here with their application to plant biology.

These terms are defined for dicots as follows: Epigeal - describes the germination process where the germinating seed raises the cotyledons above the ground where they function as true leaves. Hypogeal - describes the germination process where the cotyledons remain below ground and do not function as leaves.

All well and good. However, one is easily distracted from the biology by the use of terms referring to where rather than how.

Physiologically, this means the epigeal cotyledons power the growing seedlings by photosynthesizing. The hypogeal cotyledons support the growing seedlings by providing nutrition from stored reserves, in the way that the endosperm does; or else the hypogeal cotyledons may contribute little or nothing to the growth of the seedling, if there is some other source of stored reserve. I would expect seeds having little endosperm to germinate in an epigeal pattern. Seeds with generous reserves in the endosperm or cotyledons would not be constrained to rapidly produce a green leaf, so have the option through evolution of first building a sturdy protected plant underground.

It gets a bit murky when we try to apply these terms to monocots. Many monocot plant families have a cotyledon that never emerges from the seed, following the pattern defined for dicots as "hypogeal germination."

Some monocots produce a green shoot very soon after germination, during the first growth season. Edward McRae in his book "Lilies" defines epigeal germination in lilies (genus Lilium) in this way.

McRae defines "hypogeal germination" as that where the seed produces an underground bulb during the first season of growth but no leaf. Only after a period of dormancy, therefore in the second season of growth, does the plant produce a green leaf above ground.

McRae was writing for the average gardener. Lily experts further recognize immediate epigeal, delayed epigeal, immediate hypogeal, and delayed hypogeal germinations in different Lilium species and cultivars.

We can see the rough parallels between the dicot uses of the terms and the application of the terms to lilies. The absence of cotyledons in these lilies can cause pedants a great deal of trouble in using either of them to describe what lily seedlings do. Applying them to other monocots becomes equally problematic. Of such dilemmas are the trials of glossarists apparently made!

Incidentally, in trying to find out what these terms mean, I was told that they apply to ant foraging habits as well: Epigeal foraging in ants is above ground, hypogeal foraging is underground. I never knew that before!

I think we should ban the use of both epigeal and hypogeal from discussions of any and all monocots. Find other terms for describing germination processes in monocots. The Liliists (is that a word?) would probably revolt, if we tried.

Good gardening, from here in central Indiana


- Avoiding Chores

Not Entering Inventory Data

My favorite organizer, after my daughter, is Steph. She works here part-time in the summer in the gardens and greenhouses. Steph is a jewel! She likes to clean, so the garden office is usually clean and neat when she is working. Having a few days free over the Christmas break from college (Purdue University), she inventoried Greenhouse 4 for me, sorting all those pots by name and number and writing it all down.

Now Steph is back at Purdue, and I should be putting all that data into a spreadsheet. Maybe next week......, because I'm not sure I really want to know how many pots of Clivia and of Hippeastrum I have back there.

Not Writing My Investigator Annual Report

This is for my Trillium Speciation research project at Great Smoky Mountains National Park. The main focus of my project is the relationship between two species, Trillium erectum album and T. simile. I spent a week there in April gathering a little data. (The weather was alternating between pouring rain and plain old snow; nasty for outdoors work.) Now I have to write up my year-end report to keep the National Park Service research permit alive.

I'm not as far behind on this. I actually put the raw data into a spreadsheet last summer, so the arithmetic is already done. But I do need to think about the data, and summarize my thoughts in the report. Maybe tomorrow....

The Glossary of Plant Biology

I have declared it to be out of beta testing status now, and renumbered it to Version 1.0.0, and I will continue to add terms to it as I run across them. I suppose I may never decide that the Glossary is finished; after all, new technical terms are being invented almost daily in science. Actually, the current version number is now 1.0.1, for the moment.

At least now the urgency to build the glossary has receded, and I can think about other things in between occasionally adding a new word or two to it. If you have a term from plant science that isn't in the Glossary and you think it should be, drop me an e-mail with the word and why you want it included or what you think it means. You can find it at: Glossary of Plant Biology.

Haemanthus avasmontanus Rediscovered?

Tim Harvey mentioned in the Pacific Bulb Society list that someone in Windhoek, Namibia, had recently found living plants of the extremely rare Haemanthus avasmontanus. I guess the rediscovered colony must be in Namibia.

According to Dee Snijman in her book, The Genus Haemanthus (National Botanic Gardens of South Africa, 1984), the species was known from only a couple of specimens, collected in the Auasberge, southeast of Windhoek, in central Namibia. The flowers are white, the spathe valves (bracts surrounding the umbel) are brownish white. It is presumed to be related to Haemanthus montanus, but the present-day range of H. montanus is eastern South Africa, including the Eastern Cape Province, portions of the Free State, and into Mpumalanga (the old Transvaal region). Snijman says that avasmontanus is the closest relative of montanus.

An alternative spelling of the specific name is avasimontanus, but Snijman does not use this version. Sadly, Dee's book has been out of print for some time now.

Good gardening, from here in central Indiana


Look up technical terms in the Glossary of Plant Biology

- Repotting in Winter

Scadoxus puniceus

The Scadoxus puniceus are getting ready to bloom. One spike is all the way up, and most of the rest of bloom size have scapes starting to push up out of the bulbs. Before the flowers start to fade, this year's flush of leaves will be up. That means that this is the last possible moment for repotting this species. Seven years ago, the last time some of these were repotted, the larger bulbs were 8 to 11 cm. in circumference. Now, one I measured is 21.5 cm. around; and it is probably slightly under average size. Seven years ago, most were not yet blooming -- several bloomed the first time in February 2005. (Diameter for 11-cm circumference is about 3.5 cm, or 1.40 inches.)

A bloom-size puniceus with all its roots easily fills a 2-gallon (actually 8.3 Liters) container. They might grow even bigger, but I refuse to put any of them into larger pots than the 2-gallon size. If I hand pollinated these things when they are in bloom in February, we'd flood the world with Scadoxus puniceus seeds. Given the minimal conditions, even in the cold Northern Hemisphere, these are formidable greenhouse plants. They bloom when little else is flowering. They are sizeable. They propagate easily but slowly from seed. They seem to ahve taken 7 years from seed to flower for me. You could probably keep the seedlings growing continuously for their first two years of life in a greenhouse or under lights, and that ought to shorten the time to first flowering.

The ideal time to repot any plant that goes through a dormant phase is just as growth is starting up again at the end of dormancy. When the plant is going into its spurt of new growth, it is very resistant to stresses such as unpotting and replanting. That is when the hormones are all primed to push growth. Sometimes the plants seem to barely notice that they were disturbed.

Facebook Threat

Frank, my IT guy, informed me today that there are viruses in Facebook that will override any anti-virus protection software you can get. It's best if you do NOT ever download any pictures, programs, or anything else from Facebook. Be Warned!

On that happy thought, I bid you, one and all,

Good gardening, from here in central Indiana


Look up technical terms in the Glossary of Plant Biology

- Can You Grow Bulbs in Clay?


Here in central Indiana, we have lots of clay soil. I have tried to naturalize Galanthus in the lawn. Mowing is what eventually eliminated them, but I think not the clay soil. When planted in beds -- i.e., anywhere without grass -- they do well. I grow GG. nivalis, elwesii, and a few woronowii. They do just fine, away from grass and lawnmowers.

Note however that many species of Galanthus are simply not hardy in our climate, regardless of the soil. I've stopped experimenting with Galanthus and Cyclamen, since they are difficult to come by, and I got tired of killing them. Still, GG. elwesii and nivalis do really great here.

Lycoris, Cochicum, Sternbergia

So do Lycoris in addition to squamigera: chinensis, caldwellii, longituba, and sprengeri.

Hardy Cochicum like byzantinum, cilicicum, speciosum, and a few others are terrific here, even in the grass (if you don't mow till their leaves yellow off). My neighbors love the pink flowers in our lawn in later summer! They never complain about the "hay field" effect the unmowed patches of lawn give into early July.

Others that may seem unlikely but that do well include Galtonia, Sternbergia, most Eurasian Gladiolus, and a few hardier Crinum in protected spots (but full sun). You can't have too many Sternbergia! They bloom after the Colchicum have finished flowering.

The Lasagna Method

That said, it is not a good idea to just stick everything into plain clay soil. Add gypsum. Add sand. Add lots of composted leaves, or just pile your leaves on top of the beds when you rake them in autumn.

I make beds on top of the clay, starting with a very thick layer of rotted leaves; then put on a 2 to 4 inch layer of some decent topsoil; and finally cover with 2 inches of plain brown sand. Plant in the sand/topsoil layer (they get mixed when you try to plant anything). The roots will go down to the rotted leaves layer all on their own. I call it the "Lasagna Method."

No spading, but a bit of hauling and spreading. Outstanding drainage! But the clay is close enough that the roots can go down into it, if they need to, to find water in dry weather.

I didn't invent the lasagna method; I got the idea from one of these on-line plant groups. Try it; you'll love it.

Can You Grow Bulbs in Clay?

So, can you grow bulbs in clay? In many case the answer is yes, but you really don't have to. Use the "Lasagna Method" instead.

Good gardening, from here in central Indiana


Look up technical terms in the Glossary of Plant Biology

- Midwest Clivia Group

Clivia Get-together

I have set the date for the meeting of the Midwest Clivia Group for March 13-14th, 2010. It will again be at my place. We will plan to have a cold buffet lunch at 12 noon on Saturday, followed by visits in the greenhouses.

In hope that we will get the plants to bloom by then, this morning I turned up the thermostats in the Clivia greenhouse from 45 F nights/50 F days to 60 F nights/ 65 F days.

If you are coming, please bring along any plants you want to show us, and anything you want to trade. Let's make it a swap meet as well as looking at flowers and talking with friends.

Sunday is also available for greenhouse visits. Other Clivia Enthusiasts in the area include Rashid Qureshi in St Louis, Missouri (5 hrs west of here by car) and Kevin Akin outside Columbus, Ohio (2 hrs east by car). Both have greenhouses full of clivias.

If you intend to come in time for lunch on Saturday, March 13th, please R.S.V.P. to me: <jim@shieldsgardens.com>

Good gardening, from here in central Indiana


Look up technical terms in the Glossary of Plant Biology

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Last revised on: 26 January 2010
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