A flower head of Buttonbush.
The plant featured in this post is Buttonbush (Cephalanthus occidentalis). It grows around the shores of the lake behind our house, and it is always found in wet places around here. You can find it in the wild in zones 5-9.
The photograph above shows a flower cluster of the plant as it appeared last summer. If you look closely, you will see that the structure is actually a group of small five-sided flowers. A long style protrudes from the center of each flower and gives the flower cluster a pincushion-like appearance. Each long style has a yellowish stigma on the outer end and is attached to the ovary of the flower on the end nearest the flower cluster. Pollen must land on the stigma for the flowers to be fertilized and ultimately produce seeds. The stamens are short and do not protrude much from the petals of each flower. You may be able to see some stamens on flowers near the center of this photograph. They appear as small dark dots around the inside of each flower. Mature flower heads are 1.5 to 2 inches in diameter.
The tubular nature of Buttonbush flowers.
At a slightly more mature stage, many of the flowers have been fertilized and the tubular nature of the flowers can be clearly seen. The petals of each flower are attached to a bright green, round core at this stage. (A bonus if you spot the spider in this photograph).
A flower head of Buttonbush.
In this photograph, all the petals have fallen from the green core. The ovaries of the flowers are in the compartments of the green core, so the seeds will develop there. At this stage, the core is about 3/4 of an inch in diameter. The red color visible at the base of some flowers has been selected in some cultivars of Buttonbush so that the entire seed head is a deep red.
A nearly mature flower head of Buttonbush.
I collected this flower head just this past weekend (November 11). The larger bases of the flower head have arisen from fertilized flowers and are expanding to produce seeds. Each large compartment should produce two small black seeds. I will try to collect a later stage when the seeds are more mature and visible, but I will have to beat the birds to them.
The smaller, crowded compartments are the remains of flowers which were not fertilized.
Please note: The various photographs in this post are from different plants, so this is not a true developmental sequence of a single flower cluster.
In the last post, I illustrated the overall form of the Devil’s Walking Stick (Aralia spinosa). Now we will look at what happens to the large, light-colored flower clusters at the top of the plant.
The flowers of the Devil’s Walking Stick are tiny, and there are hundreds of them on each plant. In the photograph above, three flowers are illustrated with a flower bud between two of them. Each flower has five petals and five stamens. The petals are recurved and the anthers are still present on the stamens. The flowers are quite attractive to bees and other small insects.
The photograph above shows a later stage in flower development. The flowers have been pollinated and the base of the flower (which contains the ovary) is beginning to enlarge.
Each fertilized flower develops into a small black berry. This is such a heavy load for the plant that it is often bent over from the weight.
Here I am holding a cluster of berries, so you can get some idea of the size.
The berries are quite handsome. They are also eagerly consumed by birds.
Here is a closer of a group of berries. The remains of the stamens can still be seen protruding from the surface.
The stem of Hercules’ Club, showing thorns.
Picture this. You are walking through the woods, perhaps up a slight slope. To gain some stability you grab the sturdy-looking sized trunk of a small tree for support. Ouch! That hurt!
You have encountered the “Devil’s Walking Stick” (Aralia spinosa) also called “Hercules’ Club” with its array of stout thorns. So named because the Devil (as an aid in walking) or Hercules (as an aid in clubbing) could presumably utilize the trunk of this small tree with impunity. The stem of the specimen pictured here is about three inches in diameter.
In the photograph above, I am holding a single leaf. These leaves are three feet long or more and doubly compound. In fact, the leaves are the largest of any temperate plant native to the U.S. (of course, some palms have larger leaves, but they are not classed as temperate plants).
The Devil’s Walking Stick in flower
Devil’s Walking Stick has an interesting growth form. It has a straight, unbranched main stem with most of the leaves grouped at the top…sort of like a palm tree. In late summer, Devil’s Walking Stick is flowering, and the flowers occur in very large, white or pale yellow clusters at the very top of the plant. In the photograph above, I have added some white arrows to show the stem of the plant, and the large flower cluster is visible at the top. Later in the season masses of small purple fruits will develop from the flowers.
Look for a closer look at the flowers and fruit in subsequent posts.
Dorsal view of a Red-femured Spotted Orbweaver Spider showing the stabilimentum.
Fall is a great time to look at spiders. We have lots of them around the outside of the house. The lights inside the windows attract all sorts of potential prey for the spiders, which have constructed webs just outside the windows. The Red-femured Spotted Orbweaver (Neoscona domicilorum) shown in the photograph above is a very common species at our house this time of year. The photographs shows its red femurs clearly.
A Neoscona domicilorum spider in its web.
Here is the spider in the center of its web. I took this photograph from a web just outside our dining room window. I did not want to disturb the spider, so I could not get a good angle for taking a picture of its underside. However, I was able to photograph the underside of another spider of the same species, which was facing in toward the house (see the photograph below). This species is normally nocturnal, and takes its web down in the morning only to re-spin it late in the evening for use overnight. However, late in the season, probably because of increased food requirements needed for producing eggs, they remain in their web during the daytime.
The thicker web material immediately surrounding the spider is called a “stabilimentum”. Not all spiders produce stabilimenta, and in the spiders that do, they take a variety of forms and may incorporate a variety of materials. One of my previous posts (http://www.gkochert.com/approach-with-care/) shows the very ordered stabilimentum of a Garden Spider (Argiope aurantia).
I think it is fair to say that the function of the stabilimentum is unknown at present. Among the speculations about its function include the following: to stabilize the web in some way; to camouflage the spider; a warning to birds so they will not fly through and destroy the web; an ultraviolet light reflector to attract insects; or a storehouse for excess silk. However, sometime the species that normally produce stabilimenta will make webs without them, and they seem to function perfectly well.
Ventral view of a Red-femured Spotted Orbweaver Spider.
As mentioned above, I was unable to photograph the underside of the Red-femured Spotted Orbweaver shown in the first two photographs of this post. However, I found another web of this same species outside the living room window, and I was able to take the photograph above through the window glass. However, this web was too high for me to be able to take a photograph of the upper side of the spider without disturbing it or capturing it. So you can see the dorsal (upper) side of this species in the first two photographs and the ventral (lower) in this last photograph. The spiney nature of the legs and the white spots on the abdomen that are separated by a black band are well-shown in this last photograph also.
A Thistle Flower with Mature Seeds.
By this time of year the flowers in the thistle heads that have been fertilized have each produced a seed. Each seed is equipped with gossamer filaments that catch the slightest breeze and disperse the seed to a new location. Very few of the seeds manage to germinate into a new plant, but there are so many seeds produced that there is a good chance that some seeds will produce new plants.
Most of the younger flowers I have pictured in previous posts on this blog came from a plant that was growing on the roadside near our house. As I noted in an earlier post, that plant was mowed down by the County Highway Department. The photograph below shows a different plant which escaped the mowers by growing in a field a little way from the roadside. All the seed heads have produced seeds and the plant is dying.
A Late-stage Thistle Plant.
Maybe I am too fascinated with thistle plants, and by now I have bored you all to death with photographs of various stages in flower development. I promise this will be the last thistle post for a while. Look for the Devil’s Walking Stick in future posts!
A Male Blue Dasher
Here is another dragonfly spotted during our May visit to the Phinizy Swamp Nature Park near Augusta, GA. This is a male Blue Dasher (Pachydiplax longipennis). It was perched on the end of some vegetation along the boardwalk. This unusual perching style with the wings angled forward is characteristic of the Blue Dasher.
Dragonflies hunt their prey using different techniques. Some will patrol and catch prey on the wing when it is spotted during a flight. The Blue Dasher is reported to be an ambush predator. They perch in a likely location and dart out to capture prey that happens to pass by.
An early-stage thistle plant.
In previous posts, I have shown several pictures of Nodding Thistle (Carduus nutans) flowers, so I thought it was about time I showed a photograph or two of the plant itself. All the pictures of Nodding Thistle that I have posted so far came from the plant shown in the photograph above. It was growing along a road near our house. The plant had only early-stage flowers when this photograph was taken in May. Later the plant produced mature flowers, but shortly after that the county road mowers got it. I had to use other plants to get plants with mature seeds (see the a subsequent post for these).
Prickles on a thistle plant
The photograph above shows more detail of the rather impressive prickles growing on the stem and leaves. No wonder livestock are reluctant to graze on it!