Sunday, April 29, 2018

Callery Cedar

"...and a partridge pear in a pear cedar tree"

Barb called me a few weeks ago to tell me that she had found a Callery pear tree (think Bradford) next door that was growing out of the trunk of an eastern red cedar.  I won't go on to say what I thought at the time as she edits this blog.  As I trust her fully I only said, "Oh?"
Pear above junction with the parent cedar.
When I got home I went out to see it for myself.  Indeed, there is a Callery pear tree, Pyrus calleryana, 2.5" in diameter emerging from the cedar's trunk three feet above the ground!  It is healthy and happy, approximately 12' tall and in full bloom.  The cedar appears healthy and is the same height as its mates along the line.

Cedar limb scar with Callery pear exiting above - Click to enlarge
Base of pear- Click to enlarge
Close up you can see that a branch was sawed off years ago.  The Callery emerges from the top edge of the scar, which is 3" in diameter, on a 9" DBH (diameter at breast height) cedar.  There is no visible opening to suggest a cavity where a seed might have fallen in the past. 

The first thought might be that it was grafted.  Bradford pears like all other flowering broad-leaf trees are angiosperms and can't be grafted onto gymnosperms such as junipers and pines.  (Technically, our "eastern red cedars" are not cedars, they are junipers, Juniperus virginica.)

The current consensus** of several forestry people is that some time in the past fifteen or so years a bird passed a seed onto the branch and it landed in a crack in it.  Perhaps the bird's feces provided it a little nutrition and a break in the cedar bark allowed some water to collect.  A big question remains - does its roots extend to the ground or is it getting its nutrition from the cedar itself?  I hope to protect it until someone can study its vascular connection to either the cedar or roots extending into the ground.  Regardless of the details it certainly was a one in a million occurrence.

Callery pear trees were brought to the US in 1916 from China to combat fire blight in the common fruit pear (Pyrus communis).  Once they were found to be relatively resistant, 100 pounds of seeds were imported to develop a resistant genotype.  Over the years more seeds from across China, Japan and Korea were collected and made available to nurseries.

In 1952, the ornamental possibilities of one particular vigorous, thornless tree were recognized, and cuttings of it were grafted onto P. calleryana seedlings.  After 8 years of successful testing in nearby neighborhoods they were named "Bradford."  They are unable to self-pollinate, therefore the trees, by themselves, couldn't set fruit. Their vigor was described by USDA plant explorer Frank Meyer in 1918 who had first collected the seeds.
"Pyrus calleryana is simply a marvel. One finds it growing under all sorts of conditions; one time on dry, sterile mountain slopes; then again with its roots in standing water at the edge of a pond; sometimes in open pine forest, then again among scrub on blue-stone ledges in the burning sun; sometimes in low bamboo-jungle...and then again along the course of a fast flowing mountain stream or on the occasionally burned-over slope of a pebbly hill."
When a species is described as thriving in any condition, tolerating all enemies, and like Superman "able to leap over tall buildings in a single bound" you are describing an invasive species.  Soon there were several cultivars produced across the country and when they were planted together as my dad would have said, "up jumped the devil."

A cultivar with striking leaf color in Oregon became Autumn Blaze. Aristocrat, from seedlings growing at a nursery near Independence, Kentucky, had a strong central leader with horizontal branches and an early pyramidal form, more sturdy that the somewhat fragile Bradford.  Chanticleer, cloned from a street tree in Cleveland, Ohio, was named the 2005 Urban Tree of the Year by the Society of Municipal Arborists.

"Callery in a Cedar Tree"-  Click to enlarge
This was all well and good as they weren't self-pollinating but soon innocent insect species began moving pollen between different cultivars planted a few hundred feet apart. Their offspring began creating their own hybrids that could reproduce.  It was as though the individual varieties that had occurred natively in China had all moved into the same neighborhood and had a giant angiosperm orgy.

Callery pears and their 'Bradford' kin are now spreading wild and are considered possibly the greatest invasive plant species threat in Missouri.  In the words of Nathan Muenks* of MDC:
"It’s difficult to truly determine which invasive species is most impactful, but Callery pear sure ranks up there with bush honeysuckle, sericea lespedeza, spotted knapweed, feral hogs and a few others. The reason being that it I would consider it an “ecosystem changer.” Given its ability to invade many of Missouri’s habitat types (whether open or wooded) and the fact that it forms such dense thickets, it has the ability to drastically out-compete native flora and drive away native fauna by creating unusable space for them. It not only grows dense, it also grows quickly. In addition, it’s a tree, vs. bush honeysuckle and others, so it can tower into the upper mid-story – what hope do our native, slower growing trees have in competing for resources and regenerating our native forests and woodlands?

There is no doubt bush honeysuckle and other invasives are much more widely distributed and affecting more natural communities at this time, but there is a strong fear that Callery pear is on a very similar trajectory. While in St. Louis yesterday, I noticed that bush honeysuckle and Callery pear tended to do just fine growing together, with honeysuckle dominating the low under-story and the Callery pear towering above it – SCARY! Is this the future of Missouri’s landscape? It could very well be if we don’t halt the invasion and join in this fight together!"
I would nominate Callery pears as our most invasive plant species, pending the discovery of garlic mustard growing on the back of a zebra mussel.  I am proposing naming this Callery/cedar tree shown above, Juniperus calleryana var. Barbarae, in honor of the discoverer.

*Nathan Muenks is the Habitat Management Coordinator with the Missouri Department of Conservation.  This includes coordinating the Department’s terrestrial invasive species management efforts.

** If any other readers have a better idea about how the pear grew on the cedar, we would be glad to hear it.
Post-publication Ideas:
James Trager- Need a CT Scan of the tree.  Yes, they have been done, see this Youtube.

Tuesday, April 24, 2018

Bee Plant Wise

Urban plantings frequently include non-native plants that may not provide nectar for our native species of bees, butterflies and moths.  They usually can't serve as host plants needed for food for native caterpillars.  We encourage homeowners to "Bee Wise and Plant Natives."

Our Master Naturalist chapter is participating in the Native Plant Market at the Springfield Botanical Center on May 18th from 9:00AM to 2PM.  Our focus will be on invasive ornamental plants that are harming Missouri's wild and urban ecosystems and the wisdom of replacing them with our natives.

There's a wealth of reliable resources on the internet to help the curious (as well as the obsessed) when it's time to chose ornamental plants for our yards and public spaces.  Perhaps the first question we should ask when making decisions about plants is "Is it a known invasive or known to have invasive tendencies?"

  • Grow Native! is Missouri's best resource for all things relating to native plants, including advice for beginners as well as the experienced, pollinator and wildlife habitat, water protection, and local resources.
  • For information about invasive plants in general, their environmental impacts, and specific plants that are known to be invasive in our area check out Missouri Botanical Garden Invasive Species. 
  • Missouri Botanical Garden has a Native Landscaping Manual in PDF form.  Chapter Four is an excellent guide for gardeners wanting to landscape with native plants.
  • If you want information about control and identification of invasive species link to Chapter Three.
  • To learn more about common invasive ornamental plants, how to identify and control them see this Missouri Department of Conservation (MDC) link.
  • Native Plant Finder has information matching lepidoptera with plants.
  • The Invasive Plant Atlas of the US has lists of plants that have invaded and degraded natural areas throughout the US.
Local sources for native plants and landscaping include:
Also remember Missourians for Monarchs.

Sunday, April 15, 2018

Wildflower Walk 2018

Hannah Parker and her new pet - April 14!
The Wildflower Walk II got off to a roaring start 3 hours early with a visit from Greater Ozarks Audubon birders.  As usual they heard lots of species that don't fall in my hearing range, pointed out broadwing hawks circling that I would have thought were red-shouldered and some other cool finds, but the best one didn't have feathers.

Hannah Parker spotted the rather tattered female Monarch butterfly on our Mail Trace Road.  It patiently rode her finger for a while until we transferred it to a container.  It will be living on a potted milkweed in her house.  In spite of its arduous journey, we hope it will lay some eggs.

We reported it to Journey North which tracks the Monarch migration and it was the second one reported this year in Missouri.  The first was reported flying overhead in St. Louis.  You can see the report here.

From there on the day was a continued success.  We saw a lot more finds with the trained eyes of Michelle Bowe and her students (MSU) and Ioana Popescu (Drury). They provided lots of Greek, Latin and botanical pearls while some of us just carried the cameras and listened in awe.

Pussytoes - female
Dainty little pussytoes have just blossomed with their tiny fuzzy heads.  The botanical name Antennaria plantaginifolia is less catchy than its other common names such as plantain-leaved everlasting and ladies' tobacco.  It typically grows in acid soils on prairies, or dry or rocky slopes, and glades which are abundant along Bull Creek.

Male flowers of pussytoes
It propagates vegetatively by runners under the soil (stolons) and can occur in large clusters.  Stolons are stems that run parallel to the ground or just below the ground and form new roots and essentially new plants which are genetically identical.

I had only seen the pure white blossoms but Michelle pointed out to us that they are dioecious, i.e. male or female flowers are on separate plants.  This area had the pure white heads which are the female flowers with an adjacent patch of male flowers that have tiny brown anthers. The seeds produced by the female plants have fluffy tufts on them to aid their dispersal by wind.

For those like myself who have forgotten their flower anatomy many times, here is a refresher.

A list of wildflower species found at Bull Mills with Saturday's finds highlighted is here.

Monday, April 9, 2018

Bank Stabilization

After a moderate flood - Click to enlarge
Like many other streams, Bull Creek is challenged in recent years by larger rain events and increased flooding.  Continued development in the upper reaches of the watershed includes more impervious surfaces such as roofs and paving.  Lawns replace native grasses, shrubs and trees with deep roots that previously captured some of the rain with each storm.  This leads to larger peak flow creating increased bank erosion and gravel deposition as well as silting in of Lake Taneycomo with serious implications for the economy of Rockaway Beach.  Below you can see the changes from 2008 to 2018.

Undercut bank
When the creek gives us more water it takes away more soil.  The Christmas flood of 2 years ago and the following April flood caused a loss of 50 feet of bank in a 300 foot stretch including 6 rows of recent riparian plantings.  More important it threatened the remaining mature trees along the east bank downstream.  This is located in the middle of an 8 mile stretch of Bull Creek which is designated as one of Missouri Outstanding Resource Waters.

Dave Woods, of the Missouri Department of Conservation fisheries division designed an initial plan for stream bank remediation with the construction of a bank stabilization structure which was just completed.  The project was funded by the Missouri Conservation Heritage Foundation through the Stream Stewardship Trust Fund which is described here.

The objectives of the project were to mitigate the unnatural rate of stream bank erosion, improve the channel stability by reinforcing three light equipment stream crossings, augment and protect more than 30 acres of bottom land forest to maintain a healthy riparian corridor.  It included establishing a perpetual easement to protect over 1.5 miles of the high quality Ozark stream, its tributaries and the associated corridor.  The easement permanently protects the high quality riparian areas along the creek from unnatural disturbance and development now and by any future land owner.

This remediation involved bringing in 1,400 tons of rock to stabilize 320 linear feet followed by replanting 2.7 acres of seedlings along the restored bank.  Detailed engineering plans were created by Chris Cash and the construction work was by Kelpe Contracting, a firm that specializes in riparian remediation.

Dave and Andy harvested 8' willow and sycamore poles (logs really) and these were held upright in trenches with the bottom end below water level in the hyporheic zone, the stream water that flows under a gravel bar.  Here they will sprout roots and grow to begin the riparian tree restoration even before the seedlings are planted next spring.

The project was completed in 5 days with a pause for a flood that tested the bank which passed with flying colors.  A video of the project is at this Youtube link.  Special thanks to Dave Woods who shepherded the project through a two year gestation to delivery and to Andy Humble for his logging skills and strong back.  Many thanks to the Missouri Conservation Heritage Foundation for all they do for conservation in our beautiful state.
Downstream portion of bank stabilization - Click to enlarge
 This work was made possible by the Stream Stewardship Trust Fund through the Missouri Conservation Heritage Foundation.

Wednesday, April 4, 2018

Hydra Microblog

Microblog from Linda Bower MN

Green Hydra - Wikimedia
Linda Bower sent me this fascinating video she filmed of a green hydra in pond water.  Like the crinoids of old, it ingests nutrients into a dead end stomach, expelling undigested particles back out the way they came.  What is not to love about a simple system like that?

New to hydra?  Here's an excerpt from an article by Northern State University of South Dakota, USA: "Hydra are named after the nine-headed sea snake of Greek mythology and are freshwater relatives of corals, sea anemones and jellyfish. All are members of a primitive phylum, the Cnidaria. The gut of cnidarians has only one opening. Unlike more complex animals, cnidarians are designed around 2 sheets of tissue: the ectoderm, lining the exterior; and the endoderm, lining the gastrovascular cavity. The two are separated by a gelatinous partition...greatly expanded in jellyfish, but is much reduced in hydra."

Chlorohydra viridissima is a bright green species, owing to the presence of numerous algae called zoochlorellae, which live as symbionts within the endodermal cells. Their relationship is mutualistic as the zoochlorellae carry out photosynthesis and produce sugars that are used by the hydra. In return, the carnivorous diet of the hydra provides a source of nitrogen for the algae.

Hydra viridissima - Wikimedia
At the base of the tentacles is the mouth. Smaller animals which blunder into the tentacles are stung and paralyzed by structures called cnidocytes, the little bumps seen along the tentacles in Larry Wegmann's photograph below.  The tentacles draw the prey into the mouth, and body fluids leaking from puncture wounds stimulate a simple feeding response as the shortening of the tentacles shorten, the opening of the mouth expands, and the victim is engulfed.  Digestion of the prey item in the gastrovascular cavity proceeds over several hours. Cuticles and other undigested remains are subsequently expelled through the mouth. Almost any small invertebrates, up to the size of the hydra, may be consumed, including annelid worms, rotifers, insect larvae, and (especially) small crustaceans, such as Daphnia, Chydorus and Cyclops spp."

Hydra budding - Larry Wegmann
Most hydra reproduction is asexual by budding as seen above.  A new but genetically identical hydra is extending from the body and will break free from the parent.  Hydras can occasionally reproduce sexually.  Most species being hermaphrodites, they form both an ovary and testicles on the same individual.  A single fertilized egg can be held until the conditions are right for its release.

You can read more in the Northern State University article.

Tuesday, April 3, 2018

Blueberry Stem Gall

Mark Bower sent me this picture of a "weird thing" he found while out photographing mushrooms.  He described it as being hard and growing off of a plant.  Now when a man whose passion is photographing fungi thinks something he found is "weird" I have to take it seriously.  To me it appeared to be a deformed part of a plant stem, likely a gall.

Gall in winter - 
Using my years of Master Naturalist training and botanical skills, I Googled "kidney shaped gall" and came up with several pictures of blueberry stem galls.  That opened up a lot of references to the gall and the wasp that forms it, Hemadas nubilipennis.  I was intrigued by the name and searched for the origin of this name and only came up with "pennis" which is Latin for "feather" or an aluminum coin of Finland  eliminated with the introduction of the Euro.   But I digress.....

H. nubilipennis - John van der Linden
The wasps are tiny, measuring less than a tenth of an inch.  They emerge during the blooming season and most are females.  Following mating, a female wasp lands on a tender shoot, frequently under the leaf litter. Facing the tip, she plunges her ovipositor into the stem to deposit an egg, then moves slightly forward to repeat the action multiple times. There are typically 12 eggs in a gall.

Wasp larvae in the gall - Molly Jacobson
The eggs will hatch in 12-14 days and the damage of the larvae feeding causes the stem to swell,  producing the gall.  This provides nutrition and protection for the developing larvae.  The gall turns hard in the fall and the larvae will pupate in it in the spring.

Galls are a major problem among blueberry growers and the primary treatment is pruning of parasitized stems.  Elimination of the wasps takes persistence over years.  Although blueberries are self-pollinating, cross pollination by insects produces larger fruit.  Spraying insecticide as a secondary treatment against the wasp is tricky as the wasps emerge in blooming season at the same time as honeybee pollination.  Michigan State

Wasp emerging from a Blueberry Stem Gall - Nature Posts
There is a fantastic set of photographs of the tiny gall wasps emerging on the Nature Posts blog but they aren't all of the gall with H. nubilipennis.  It turns out that at least 6 other parasitic wasps call these galls home.  One is a chalcid wasp called Ormyrus vacciniicola.  I went straight to Charley Eiseman's Bugtracks where he describes two more eurytomid wasp species that are known to parasitize Hemadas nubilipennis exclusively,  Eurytoma solenozopheriae and Sycophila vacciniicola.  This is where it gets really weird.  He goes on to say:
"Eupelmus vesicularis (Eupelmidae) has also been reared from these galls, and by contrast is one of the least host-specific chalcidoids–its known hosts include six different orders of insects.  It is thought to have been introduced from Europe in straw, and the list of host species in North America is said to be “tiresomely long.”
So of my gall emergences so far this year, one in four has been the actual gall inducer, and the rest have been parasitoid wasps.  I think this is pretty representative of what’s going on out there–there seem to be more parasitoids than anything else.  Hemadas nubilipennis galls are multi-celled, so it will be interesting to see what else comes out of the ones I collected." - Charley Eiseman
We haven't identified many blueberry plants in our valley and I wonder how the wasp found a victim.  We will start looking more carefully for other plants.  Details on the lowbush blueberry are at  For an interesting history of the blueberry stem gall read pages 14-17 of this 1981 Ospry newsletter.
Some of the findings from MN Wildflower Walk I are at this link.  WW II (not the war) is on April 14th at 1PM.