Sunday, April 20, 2014

April 17 2014 Ramble Report



Twenty Ramblers assembled on this chilly morning – what happened to spring?


First up was an important announcement: Hugh and Carol are this year’s recipients of the Alec Little Environmental Award, to be presented this evening (April 17) at the Athens GreenFest Awards Ceremony.

Today’s reading was a short piece pertinent to the season:

Gazing in the distance you will now see a long-awaited green mist, the stirring of tree leaves emerging from their buds. Soon we will be able to hear them rustling in the wind and this soft sound signals a change in the short life of the ephemeral flowers on the ground below. The closing of the canopy deprives them of sunlight and they must rush to produce their fruits and seeds and the
n retire until next spring.
Dale Hoyt, April, 2014


I pointed out the remains of the male “flowers” on the Ginkgo tree near the arbor. (Flower is in quotes because the Ginkgo is not a flowering plant. It is a distant relative of the pines, classified in its own plant phylum, Ginkgophyta. All the Ginkgos in the US today are descendants of a few trees found in Buddhist temples in Japan and China. There are, apparently, no surviving natural populations anywhere else. Ginkgo trees are dioecious, meaning that the tree is either male or female. Only male trees are usually planted because the fruits of the female tree are so foul-smelling when stepped on.)

The route today was from the parking lot, down the walkway through the Shade Garden, from which we wandered through the Dunson Native Flora Garden and returned back through the Shade Garden.

Shade Garden Walkway:
Alongside the walkway we found several plants blooming: Solomon’s Seal (a cultivated variety with variegated leaves), Spanish Bluebells, and a single individual of Trillium discolor, an escapee from the Dunson Garden.

Spanish Bluebells -- pretty plant, pretty invasive
The Spanish Bluebells are invasive. Earlier this week some of our Rambler volunteers spent 21 man hours digging them up from the Dunson Garden.

Witch Hazel nipple galls

Split gall showing brown aphid inside
We also stopped to look at the “nipple” galls just now appearing on the American Witch Hazel tree leaves. This gall is produced by an aphid. The aphid lays an egg in the emerging leaf tissue and this causes the development of the nipple gall. Inside the gall the egg hatches and the newborn aphid inserts its sucking mouthparts into the leaf tissue to feed. Earlier I split open a gall to reveal its single inhabitant. This single aphid will asexually produce many offspring inside the gall. Some of them will develop wings and emerge from the gall and fly off to a different host plant. Right now the galls have no openings, but last year, at a later time in the year, we looked at these galls and discovered that they were open on the lower surface. How the opening is made is a mystery.
 
Many plants in the Dunson Garden are in bloom and we spent the reminder of our time there today. Some of these plants were in bloom last week, so I’ll comment on the latest bloomers unless there are new observations to make. The list of all the plants observed is found at the end of this post.


New York Fern
New York Fern is recognized by the shorter pinnules at both the bottom and the top of the frond. The mnemonic is that New Yorkers burn their candles at both ends. (If that helps you to remember it, fine. If not, make up a better one and share it.)


Cinnamon Fern
Cinnamon Fern has two types of fronds, sterile and fertile. The fertile fronds are tall and bear cinnamon-colored sporangia. The sterile fronds are green and lack any reproductive structures.
Golden Seal
Golden Seal is a medicinal plant.


Painted Buckeye flowers
Painted Buckeye is hummingbird pollinated, even though the flowers are not red in color. 


Mayapple flower
Mayapples only bear flowers when there are two leaves on the stalk. Plants with a single leaf will not flower.

Silverbell flowers
Common Silverbell is an understory tree that typically is found in moist situations. The bark of young trees has a unique green striped appearence.

Wild Chervil
Wild Chervil or Cow Parsley is sometimes confused with Corn Salad, but the leaves are very different. The Chervil leaves resemble those of carrots, whereas Corn Salad leaves are not finely dissected.

Field Madder
Field Madder can be mistaken for a type of Bluet with a casual look. Both have tiny, pinkish four-lobed corollas. But Field Madder has whorls of six leaves surrounding its stems, which Bluets do not.


Toadflax flower
Blue Toadflax has an unusual flower with a long, curved spur. In many flowers the spur holds nectar, forcing a pollinator to reach deep into the flower and come in contact with the anthers and/or stigma. What insect would be able to reach this spur? I can only think that some butterfly might be able to do it -- they have long, tubular "tongues" that can suck up nectar. Someone has to sit and watch the plants to see if this is the case.

Conservatory Mealy Bug Control Project

Mealybug Destroyer larva

Mealybug eggs (brown), larvae & adults

 Some Ramblers were able to see the Mealybugs that are infesting some of the plants in the conservatory. The garden staff are attempting to use biological control to limit the infestation. They are using a beetle that is related to Ladybugs and is a voracious predator of Mealybugs. Both the adults and the larvae of the beetle eat all stages of the Mealybug. Don Hunter captured some photos of both the predator and the prey. The beetle is named Mealybug Destroyer (Cryptolaemus montrouzieri); its larva resembles the Mealybug itself.

As usual, we ended the ramble with beverages and conversation at Donderos'.
 
SUMMARY OF OBSERVED SPECIES:
Common Name
Scientific Name
Comment
Ginkgo tree
Ginkgo biloba

 American Witch Hazel
Hamamelis virginiana
nipple galls
Solomon’s Seal
Polygonatum odoratum
Flowering
Spanish Bells
Hyacinthoides hispanica
Invasive
Small Yellow Toadshade
Trillium discolor
Flowering
Wild Geranium
Geranium maculatum
Flowering
Columbine
Aquilegia canadensis
Flowering
Piedmont Azalea
Rhododendron canescens
Flowering
New York Fern
Thelypteris noveboracensis

Cinnamon Fern
Osmundastrum cinnamomeum
fertile fronds present
Chattahoochee Trillium
Trillium decipiens
Flowering
Sulfur Shelf Mushroom
Laetiporus sulphureus

Blue Haw
Viburnum rufidulum
Buds, but no flowers
Threepart Violet
Viola tripartita
Flowering
Green and Gold
Chrysogonum virginianum
Flowering
Virginia Bluebells
Mertensia virginica
Flowering
Perfoliate Bellwort
Uvularia perfoliata
?
Small-flowered Paw Paw
Asimina parviflora
Flowering
Early Meadow Rue
Thalictrum dioicum
Finished flowering
Black Cohosh
Actaea racemosa
No flowers
Bloody Butcher Trillium
Trillium recurvatum
Flowering
Shooting Stars
Primula meadia
Formerly Dodecatheon
Yellow Trillium
Trillium luteum
Flowering
Spider Lily
Lycoris radiata

Native Azalea
Rhododendron austrinum
Lisa’s Gold cultivar
Leatherwood
Dirca palustris
No longer flowering
Dwarf Crested Iris
Iris cristata
Flowering
Golden Seal
Hydrastis canadensis
Flowering
Small’s Ragwort
Packera anonyma
Flowering
Foam Flower
Tiarella cordifolia
Flowering
Rue Anemone
Thalictrum thalictroides
Flowering
Painted Buckeye
Aesculus sylvatica
Flowering
Mayapples
Podophyllum peltatum
Flowering
Common Silverbell
Halesia carolina
Flowering
Wild Chervil
Chaerophyllun tainturieri
Flowering
Unidentified Red Mushroom


Beaked Corn Salad
Valerianella radiata
Flowering
Field Madder
Sherardia arvensis
Flowering
Blue Toadflax
Nuttallanthus canadensis
Flowering
Goose Grass, Cleavers
Galium aparine

Dooryard Violet
Viola soraria
White morph
Sweet Shrub
Calycanthus floridus
Yellow flowered Cultivar