Friday, October 26, 2012

Epitaph to a Tree?

The little green menace has now been found in Greater Kansas City!  Emerald Ash Borer (EAB), a tiny beetle from Northeastern Asia, has been confirmed in Platte and Wyandotte Counties.  What's the big deal? EAB kills all Ash trees and thus all the wild creatures dependent upon them.  There are 4 species of Ash tree native to Missouri and Kansas and nearly 400 species of insects dependent upon them alone.

White Ash (Fraxinus americana) is one of two species of ash trees native in Greater Kansas City statewide in Missouri and in the eastern third of Kansas.  It grows in upland woods and is known for being one of the very best local trees for consistent fall color.  White Ash turns colors early and stands out in the woods -- usually purplish to begin with it can look like it is on fire with yellower tones inward changing to oranges, reds and purples on the outer leaves.  As homeowners tend to choose trees for fall color, it is very popular in landscaping.  'Rosehill' is a cultivar of this native tree by our local Rosehill Nursery, while the cultivar 'Autumn Purple' is another popular selection of this tree with more purple fall color.  The White Ash in the above image is a wild tree at Powell Gardens.

Green Ash (Fraxinus pennsylvanica) is the other locally native ash tree and found statewide in both Kansas and Missouri.  It thrives in low or bottomland woods but is very adaptable to soils wet to dry.  Its tough adaptability has made it a good urban and street tree where it thrives even with concrete all around its roots.  Green Ash turns yellow in the fall, never orange or red.  The picture above is of a Green Ash planted in Powell Gardens' parking lot arboretum of trees native to Kansas and Missouri.

This little tree with nice fall color is on the south side of the Visitor Center and is a third species of ash native to our MO-KAN region but found wild only in Southeast Missouri: Pumpkin Ash (Fraxinus tomentosa).  Pumpkin Ash has fall color usually in shades of orange.  It grows in swamps and can actually survive growing in water, developing a swollen, buttressed trunk -- Chuck Connor, MDC Urban Forester told be that swollen base is the "pumpkin" and how it got its name.  It is otherwise similar to White Ash but its twigs are covered with gray fuzz (known botanically as tomentum and how it got its botanical name).

Blue Ash (Fraxinus quadrangulata) is the fourth species of native Ash and is found on the east and south edge of the metro eastward across Missouri and Southeastern Kansas. Its twigs are square and its late fall color is clear yellow (still green as this picture from this morning shows).  It is called Blue Ash because its sap turns blue when exposed to air and can be used to make a blue dye.  It grows almost exclusively in rocky woods and ledges so needs good drainage wherever planted: the local champion tree is in Loose Park and Powell Gardens largest tree is depicted above by the old Visitor Center with more trees in our parking lot arboretum.

Emerald Ash borer will not harm you, your family or your pets but it KILLS ALL SPECIES of ASH trees native to our region (White, Green, Pumpkin and Blue Ash but NO other species of tree).  Dead ash trees can harm you, your family and your pets.

Ash trees make up about 4% of all trees in Missouri but a much larger percentage in Kansas where they are the third most abundant tree.  Overland Park's tree inventory shows ash make up 23% of its street trees.  The tallest orange tree just to the left of the chapel in the above image is a White Ash.  At Powell Gardens ash numbers closely match the Missouri's average.

Over 400 species of insects require ash trees for their survival.  Do we depend on ash trees for our survival?  I'll start with some statistics of what ash trees do for us in Greater Kansas City where 6.5 million ash trees are estimated to reside, 3 million of them are in our residential areas.  The value of our local ash trees is over 4.5 BILLION dollars!!!  Their value is based on their ecological services starting with how much stormwater they intercept before it runs into our antiquated and stressed stormwater systems, and by reducing stream flooding.  It also includes their pollution control as they not only trap particulates but have sequestered well over half a million tons of carbon dioxide, absorbing another 23,000+ tons every year.  Their leafy shade save on summer cooling costs and even their leafless winter presence helps with holding in heat.  Obviously they provide us with a lot of fresh oxygen to breathe as byproduct of their photosynthesis.  How do we assign a value to their added beauty to our community and the tiny creatures they support?


This beautiful, large caterpillar is an image of one of the creatures that will suffer without ash trees in our region.  It's the Laurel Sphinx which may eat laurel where that plant is native in the East but over here where there is no laurel its sole native food plants are ash trees.  Its adult moth is a sphinx moth that flies with hummingbird-like grace and I will say I've never seen the nocturnal moth though I find its beautiful caterpillars.  This image is by Missouri Master Naturalist Linda Williams.
 


This moth is actual size and looks just like bark to avoid predators while at rest.  It is an Ash Sphinx that flies just like a hummingbird but only at night.  Without alive ash trees this moth will become extinct because that is the only plant its caterpillars are designed to eat. This image also by Linda Williams.

Here's another ash dependent moth, the Waved Sphinx.  Sure, it's doesn't have bright colorful wings as it needs to blend in with bark all day.  My favorite aspect of it is that each individual moth has a different face-like pattern on its back (thorax) outlined in a black circle.  Photo by Betsy Betros.

Here's a different Waved Sphinx with a closeup of its back: sort of a puppy face on this one.  Photo by Betsy Betros.

The Waved Sphinx's caterpillar looks an awful like our pesky tomato and tobacco hornworms, and yep they are related.  I dare you to try and grab this caterpillar!  Unlike docile tomato and tobacco hornworms, Waved Sphinx thrash and BITE!  This caterpillar was found on an Green Ash tree in Overland Park and taken indoors and photographed by Brett Budach.  Why should we care if there are no ash trees and thus none of these sphinx moths?  I may let you ponder that for a future blog, and I've only depicted 3 of the 400 species of insects tied to ash trees and we don't have a picture of the BIG DADDY of sphinx moths: the Great Ash Sphinx. (Don't forget our annual Festival of Butterflies where we hope to share with you these cool creatures in person)

Wendy Powell recently said to me "the 'Rosehill' White Ash were simply stunning along Ward Parkway this fall" and that she hoped "it wasn't their swan song".  Good news is you can treat and save your ash trees and I'll write more about that later.  Start by identifying if you have ash trees on your property.  A lot is at stake for us to save these beautiful trees, the wealth of creatures they support and don't forget that includes us.  Here are some links to learn more about EAB and we will have more information on our website soon:

National Website www.emeraldashborer.info
Missouri EAB Website: www.eab.missouri.edu
Kansas Department of Agriculture Website: www.ksda.gov/plant_protection/content/379



Thursday, October 18, 2012

Fall Color Pageant

We are thrilled to report that the fall leaf colors this season have beat expectations!  The rains from Isaac and cool nights have combined to revive plants enough to put on a beautiful display in the gardens.  I was busy capturing images of the spectacle early in the week and asked horticulture staff to report any beauties I may have missed.  Here's a look at some surprises and the stars in the show (the winner of the pageant is at the end):


Black Walnuts (Juglans nigra) are not usually known for their spectacular fall color but this year they put on their best show I have ever seen.  Lumbermen love walnut trees for their high quality timber, chefs for their oil rich nuts with a very unique flavor, naturalists for the wealth of nature they sustain; but vegetable gardeners hate them for their natural herbicide juglone that makes cultivating tomatoes near them impossible.  One thing missing this year from walnut trees were webworms -- unsightly to us but a feast for Yellow-billed Cuckoos, a bird that feasts on such hairy caterpillars. The cuckoos left the region early, the webworm moths apparently victims of the drought.  You may be celebrating their demise but their loss does hurt the natural web of life this common tree brings to our region.  One of those unknown consequences of the drought...

The Swamp White Oaks (Quercus bicolor) cloaked themselves in rich tan -- these oaks are not known for their fall color but more their magnificent stature of broad spreading limbs and tolerance to disturbed soils making them currently the most popular street tree and the tree chosen for the 9-11 Memorial in New York.  This is our magnificent specimen on the hairpin curve of the Dogwood Walk.


Maples are loved for their spectacular red fall colors and here are a pair of our Autumn Blaze Maples (Acer x freemanii) blazing better than we've ever seen.  This maple is a natural hybrid between the Red Maple (Acer rubrum) known for it brilliant red fall color and the Silver Maple (Acer saccharinum) known for its fast growth, hardiness and adaptability.   Since most homeowners select a tree based on its fall color, and want instant gratification, this tree has become quite popular.  It is still not a great long-term choice and how it will fare here for future generations is unknown.

This Post Oak (Quercus stellata) has brilliant red fall color too and is a much better choice than a maple for a long term shade tree.  It's problem is it is not available from most nurseries as it is slow to start, even though once established it has proved to us it can put on good growth every year and shrug off heat, drought, wind and ice.

Here is the copse of 3 of Post Oaks in the Parking Lot Arboretum the above closeup image is from. These were planted as small 3 gallon trees from Forrest Keeling Nursery 14 years ago and they are now 15 feet tall.  Post Oaks are quintessential Lower Midwest trees -- the magnificent tree in front of P. Allen Smith's new home in Arkansas.  They easily live 300 years and are a top tree for wildlife, if you must plant a maple for instant gratification, be sure and plant one of these too for our future.

The Blackgum or Tupelo (Nyssa sylvatica) is an almost screaming scarlet in the Perennial Garden.  This tree is known from New England to the Ozarks for its simply fabulous fall color.  It is a bit of a trick to grow here as you must have good soil and a bit of irrigation helps it though the worst droughts.  It makes a stellar garden tree and is dioecious -- either male or female: this is a male (sans fruit).

Here's our female Blackgum near the Perennial Garden Arbor.  She produces lovely blue-black fruit many birds will relish later in the season.

Fall color is also renown in shrubs and YES, there is pink fall color!  This is a seedling Arrowwood Viburnum (Viburnum dentatum) in the Rock & Waterfall Garden.  Arrowwoods are native to Missouri and often when they are grown in shade, they develop this unique pink fall color.  Our 'Redwing' Cranberrybush Viburnums (Viburnum trilobum) in the Rock & Waterfall Garden are also pink now.

This is not the best picture but I have to show off the one shrub whose fall color is almost white!  It is the very little known Japanese Orixa (Orixa japonica) whose fall color is always a very pale yellow.  This shrub is in the Rue family related to our wild Prickly-Ash but not prickly and has very glossy almost lacquered looking leaves in spring.  If you like butterflies it is host to our largest butterfly the Giant Swallowtail.  Look for this plant in the Perennial Garden's Woodland Section.
The Bottlebrush Buckeyes (Aesculus parviflora) are also a rich yellow now.  This huge shrub has giant candles of white flowers in mid-summer but puts on a great yellow fall color display in the understory shade of the Rock & Waterfall Garden and the Woodland Section of the Perennial Garden where this image was taken.
Flowering Dogwoods (Cornus florida) are still our finest plant for consistent and long lasting fall color.  This is the cultivar 'Spring Grove' along the dogwood walk. Dogwoods fall foliage holds and gradually becomes redder until the leaves finally drop, usually in early November.
The "winner" so-to-speak (there is no official contest but maybe we should make one for visitors to fill out at the front desk) of 2012's fall color display so far is the Diane Witchhazel (Hamamelis x intermedia).  Our plant is still young and in the shade of the Rock & Waterfall Garden and every year this plant has riotous fall color beginning with a purple edge to a green leaf then aging to above with a simply gorgeous blend from yellow to near purple.  Diana Witchhazel is a small tree/large shrub growing to 15 feet or so with spidery reddish flowers that open in late winter to the delight of winter weary gardeners.
So here's an overview of the colors of Powell Gardens with the east side of the Island Garden in the image.  There are still many beautiful flowers of fall along with the berried treasures in the previous blog.  The weekend is supposed to be spectacular weather so we hope you come out and see the pageant of fall colors on display now at Powell Gardens.
 
 

Thursday, October 11, 2012

Fall Fruit and the "Berried Treasures" of Powell Gardens

We had a hard freeze at Powell Gardens down to 29F!  Tender flowers have now given way to those hardy flowers and fruit of fall that are oblivious to the tribulations of Jack Frost.  Here's a post of some of the gardens' plants with ornamental fruit that add color and seasonal charm to our garden in Indian Summer.

Viburnums are well-known for their ornamental fall fruit and this 'Asian Beauty' Linden Viburnum (Viburnum dilatatum) that is a perennial winner for red fruit -- even after this last horrible summer!  Linden Viburnum is native to Japan and can escape east of here, but its seedlings are held in check by our often droughty summers.  Look for this Viburnum south of the Visitor Center.

Hollies are probably the most well-known of fall (and winter) fruiting plants because of their appeal for holiday decor which they deserve!  The evergreen hollies' fruit has finally turned red for the season and here is a picture of 'Greenleaf' hybrid American Holly (Ilex x attenuata) growing near the Visitor Center.  This is a hybrid between the true American Holly (Ilex opaca) and the Dahoon (Ilex cassine) native to the Gulf states.  It displays hybrid vigor and can grow several feet in one year , but it is also touchy to a  severely cold winter and susceptible to iron chlorosis (note these leaves are a bit yellow) in our soils.  It's a beautiful plant in a sheltered site with acidified soil.

Here's a branch of one of my favorite crabapples: Zumi Crabapple (Malus x zumi 'Calicarpa' now Malus sieboldii) on the Island Garden.  Its tiny red crabapples are stunning against yesterday's incredible blue sky.  These tiny apples are edible to us but a favorite of songbirds to eat in late fall and winter.  Birds can see color so many small fruits are showy red so they will entice birds to spread their inner seeds far and wide.  Zumi Crabapple becomes a large crabapple (20 feet tall plus) with great character as it ages.  It is currently out-of-favor to grafted dwarf selections that are just not that appealing to me -- so many of the new ones look like retarded lollipops in my mind.  They do make sense in a small landscape where space is a premium.

Here's one bigger red fruits: a 'Wonderful' Pomegranate (Punica granatum) in the Heartland Harvest Garden Vineyard.  Pomegranates have been grown by humans as food since time immemorable (there's no bird that can gulp down this big fruit!).  Pomegranates are currently very popular for their very nutritious and healthy juice rich in anti-oxidants and other compounds.  Kansas City area gardeners should know it also does well here if grown in a container and brought in for just the coldest part of winter.  We leave ours out until temperatures are predicted to fall below 20F (they are hardy into the 10'sF).  You can just put them into a garage for storage in the coldest months as they are deciduous.  In spring put them back outside and they will have brilliant scarlet flowers followed by the beautiful (and delicious) fruit.

Persimmons are one of the largest true berries we have in the garden.  This is a 'Ruby' Persimmon (Disopyros virginiana) selected for its larger fruit than wild persimmons.  They are over 2" across and finally starting to ripen -- this variety's leaves were killed by our freeze but the fruit are only made better by the cold.  Look for this persimmon in the Heartland Harvest Garden just past the Apple Celebration Court on the left (south) side of the path.
 
Here's another Crabapple but this time with bronzy orange crabapples which, like all apples, are called pomes and not berries.  It's the Tea Crabapple (Malus hupehensis) which frames the west/Visitor Center entrance to the Island Garden.   These are another favorite crabapple of mine growing into a beautiful vase shape but also growing quite large over time.  They are called tea crabapples for 2 reasons that I have read: 1) because you can make an actual tea from their leaves and 2) because ancient trees create beautiful spaces to have a tea ceremony under in their native homeland of China.  They can live a long time (100+ years) and future garden visitors may enjoy quite a space created by them as they arch over entrance seating area to the Island Garden.  It just reminds me how young Powell Gardens is (25 years old next year) -- my what a garden it will be in 2112!!

On the opposite end of the color wheel we have a few berries in the cool colors like these Northern Bayberries (Myrica pennsylvanica).  Botanically speaking these fruit are drupes like a plum and yes they are the waxy fruit used in making bayberry candles (it has another common name "candleberry").  Bayberries are dioecious so are either male or female and obviously this is a female plant with fruit (I always look for berries when buying one in a nursery and make sure you get at least one male for pollination).  The aromatic leaves can be used as a substitute for bay leaf in cooking but I just enjoy this plant for its lovely aroma when brushed or given off on a warm day.  Bayberries can be found in several locations around the garden including the Perennial Garden arbor where they have grown huge to the Heartland Harvest and Island Gardens.  These berries too are loved by songbirds in the winter.

Here's another viburnum with some of the most beautiful blue fruit: the Witherod or Possumhaw Viburnum (Viburnum nudum).    There are many selections of this viburnum on the market but beware that 2 varieties are needed for cross pollination and full fruit set.  These fruit are so beautiful through the whole season: they start out beautiful sage green and gradually change, one-by-one, to pink; then they gradually mature to blue!  After a freeze they are blue and shriveled like in the picture and are actually edible.  Another common name for this beautiful shrub is "wild raisin."  'Brandywine' and 'Winterthur' are popular available varieties but this one was just bought as a pollinator with no named variety and is growing on the edge of the Fountain Garden.

The blue fruit of Arrowwood Viburnum (Viburnum dentatum) is also a stunner in late summer into fall with its blue fruit that are now gradually wearing off their waxy "bloom" so changing color from blue to black.  This is another plant great for birds but it got its name because shoots of the plant were tough and straight so used for arrows.

So enjoy Powell Gardens in its beautiful fall splendor of "berried treasures" -- fall color is beginning and should be peaking in a week or two -- we'll keep you posted for that.
 

 

Friday, October 5, 2012

Experience the Harvest

The Harvest Celebration & Antique Tractor Show will be the highlight of this weekend at Powell Gardens.  A widespread frost or freeze also looms but we are still not under a freeze watch on this side of the state line.  The Heartland Harvest Garden staff are busy preparing the harvest for the visitors to experience the bounty of the garden as well as preparing the garden for a potential freeze.


Barbara Fetchenhier is de-stemming tomatoes harvested to beat the freeze.  Gardeners have been bringing in a bounty of frost tender tomatoes, peppers and eggplant.

Here's a closer look at a box of freshly picked tomatoes, peppers and eggplant.  It makes me hungry just looking at this colorful harvest.

Here's Barbara with a batch of fresh ratatouille made from the harvest.

Heartland Harvest Garden Horticulturist Matt Bunch digs peanuts before a potential freeze.  Yes, peanuts are produced underground!  Not from the roots but from above ground flowers that burrow underground to produce the fruit.  How's that for a plant nut!

Here's a closeup of the peanuts.  You can see they are attached back up to the above ground part of the plant and not the roots.  The roots have nodules with nitrogen fixing capabilities as do most legumes.  Anyone with peanut allergies are not to fear the plant, only the processed peanut can cause the allergic reaction.

Speaking of nuts, be sure and drop in the Good Earth Workshop in the Missouri Barn.  Here you will see a display of some of the nuts of the Heartland Harvest Garden.

Crack yourself some hazelnuts to sample from the garden (note safety glasses provided).  Our hazelnut shrubs had a great year this past summer.

Hardy Almonds always are a surprise product from the Heartland Harvest Garden.  They are actually Peach-Almond hybrids (Prunus x amygdalopersica) and make beautiful trees with gorgeous pink flowers in spring and almonds in fall (cultivars 'Hall's Hardy' and 'Reliable').  True almonds (Prunus dulcis) are not as hardy but we are trialing some very hardy cultivars from the Ukraine.  Remember peach pits are poisonous!

Pine nuts are another garden surprise!  Pinjons are well-known pine nuts from New Mexico that don't do well in our climate but others like the Lacebark Pine Pinus bungeana produce delicious pine nuts!  We only have one cultivar of Lacebark Pine in the Harvest Garden so not many of the nuts have pollinated very well so there are many "blank" (empty) nuts.  Come out and try one!  We need to plant a couple more lacebark pine seedlings or other varieties to help pollinate for the future.

The Good Earth Workshop also has a display of our hardy oranges (Poncirus now Citrus trifoliata).  Barbara has made a wonderful drink from them for you to taste.  It reminds me of grapefruit juice.  To make the drink Barbara de-fuzzed the fruit and then used the juice and zest of the rinds for a very flavorful refreshment.

Here's a picture of our hardy orange tree and how loaded it was with fruit this year.  It is just south of the Visitor Center and is the cultivar 'Flying Dragon' which has unique spiraled branching.  We have many hardy oranges planted in the Heartland Harvest Garden and we expect them to start producing oranges soon (they are just 5 years old and grown from seed). 

Even if we happen to get a freeze Sunday morning don't be afraid to visit the garden.  I guarantee it will be filled with "berried treasures" like this Victoria Southern Magnolia and we have many flowers and edibles that are freeze resistant on display, not to mention fall color that is beginning.  So bundle up with the predicted temperatures in the 50's and enjoy the crisp autumn air; tastes, sights and sounds of the garden and don't forget to walk the Visitor Center allee to see all the unique antique tractors too.