Wednesday, July 31, 2013

Conservatory Chronicles: Just Two Leaves on This Conifer

The welwitschia is coning in the arid house of the conservatory. If that sounds like a ceremony involving some kind of dark magic, no need to worry. Welwitschia mirabilis, otherwise known as the tree tumbo (its Angolan name), is actually a plant found in arid regions of Namibia and Angola.

Welwitschia mirabilis in Namibian desert (Image: Andrew McRobb, RBG Kew)

Bearing a species name that sounds like a miracle, welwitschia is named after the Austrian botanist Friedrich Welwitsch, who discovered it in 1859. Welwitsch saw the plant in the Namibian desert and reportedly fell to his knees, experiencing a mixture of awe and fear, “lest a touch should prove it a figment of the imagination,” according to the Kew Royal Botanic Garden website.

Another botanist, Thomas Hooker, proposed the botanical name to honor Welwitsch (genus) and mirabilis (species), the species name referring to its extraordinary, wondrous appearance. Though it looks somewhat like a bedraggled or shriveled green ribbon, the tree tumbo is a conifer that is dioecious, meaning there are male or female plants. Welwitschia has only two leaves, which grow out from its base. There are individual welwitschia in the wild thought to be 1,000 years old.

In times of drought mammals such as oryx, springbok, the endangered Hartmann’s zebra, and the critically endangered black rhino chew on tree timbo leaves for moisture, the Kew website states. Reptiles use the shade it throws to shelter themselves from the hot sun.

Ecologically welwitschia is highly specialized. It grows under conditions where it receives regular fog that provides moisture, and it has a deep taproot to reach moisture in the desert. The IUCN (International Union for Conservation of Nature) rates this species as “near threatened.” (The IUCN states that 1 in 5 species of plants in the world are threatened with extinction.)

Recently scientists have discovered a fungal pathogen that infects the female cones; the fungus subsequently reduces seed viability. 

Check out this very unusual desert-dwelling plant in the arid house of the conservatory at Matthaei Botanical Gardens!

The conservatory is awash in bloom, by the way.  (Remember the welwitschia is a conifer so it doesn’t count!)

Look for these plants in bloom:

Rangoon creeper (Quisiqualis indica) - on the east balcony of the tropical house.
Rangoon creeper (Quisiqualis indica)

The Malaysian orchid tree (Medinella magnifica)---not an orchid at all!
Malaysian orchid tree (Medinella magnifica)

The Umckaloabo (Pelargonium sidoides) in the northeast herb display bed.

The bat flower (Tacca chantrieri)

Tuesday, July 16, 2013

The Campus Farm at Matthaei Botanical Gardens, a Living Classroom

Campus Farm Manager Parker Anderson poses in front of one of the honeybee hives in the area he calls a "bee sanctuary."
Campus Farm Manager Parker Anderson is a gardener on a mission. Anderson, a dual degree master’s student at U-M (Sustainable Systems and Landscape Architecture), has been hard at work at the Farm this summer creating a laboratory of sustainable agriculture in a modest plot on the Matthaei Botanical Gardens property.

The project fills an educational gap, says Anderson. “Students have a need to connect to local food,” he says, “and our farm offers the side benefits of learning and community.” Students can take away ideas for how to create gardens and how to grow food locally and sustainably, he adds, desires borne out in a recent survey of U-M students.

An herb spiral. The idea of the herb spiral is both aesthetic and biological/horticultural. The spiral creates microclimates—in the case of this spiral it does so through the use of materials such as stone that hold heat longer. For the spiral, Farm manager Parker Anderson used salvaged pieces of concrete and set them upright. The herb spiral itself is a popular permaculture feature. It often starts higher---in the middle---than the outer rings of the spiral and slopes down toward the edges.

The “seed bank” at the Campus Farm lets manager Parker Anderson know what was growing in the plot in the first place.

Anderson has incorporated the principles of permaculture into the Campus Farm. A significant goal of permaculture is the development of agricultural systems that are based on natural ecosystems, in effect mimicking nature’s designs. You can see that concept in action in the area devoted to honeybees and pollination Anderson calls the “bee sanctuary,” and the future plans for a “food forest”—a plot of food-producing and nutrient-enhancing plants—near the Farm. Other elements, like the herb spiral and potato snake, are as much about artful delight as they are horticultural, says Anderson. And soon, he hopes, the farm will grow enough herbs to supply the U-M Dining Services. If you haven’t been out to the Farm yet, stop by any time the Botanical Gardens is open. And look for announcements on the Matthaei Botanical Gardens & Nichols Arboretum website about seasonal farm-related events like the fall 2013 Harvest Celebration and other programming.

The Campus farm is always looking for student volunteers. If you're interested in helping out, please contact Parker Anderson at campusfarm@umich.edu.

Farm Manager Parker Anderson is experimenting with different kinds of bed coverings or mulch to see which ones work best, what effect they have on unwanted plants, and how the mulch benefits---or not---the intended plants. Anderson has covered some beds with wood chips, some with straw, and some with no mulch at all.

The potato snake is designed for aesthetics and also to prevent weeds. Newspaper is laid down in a design (in this case, a snake), then seed potatoes are laid on top, followed by alternating layers of compost and straw. There will be three levels altogether. Potatoes spout through many layers and when covered produce more potatoes.

The future "food forest" is an area beyond the fenced perimeter of the Farm. A food forest is a gardening or land management technique that mimics a woodland ecosystem but uses edible trees, shrubs, perennials, and annuals.  Fruit or nut trees are at the upper level; below, berry-producing shrubs, edible perennials, and annuals are planted. Companion or beneficial plants are included for natural pest management while some plants amend the soil, providing nitrogen and mulch. Together these plants form an ecosystem capable of producing high yields with less maintenance.

This plastic-covered bed acts as a hothouse that bakes any plants or seeds underneath. It's an experiment in weed control: next year, with all of the  plastic-covered plants and seeds killed off, there will be fewer weeds.