Correctly identifying plant species can be a challenge, even for experts. Sometimes small features of a flower, leaf, or other plant structure are very helpful in differentiating one species from another. An example of this is the umbo on a pine cone scale.
In biology, the word "umbo" refers to some type of bump or protrusion. On pine cones the umbo is a bump at the end of each individual cone scale. Umbo location and size vary among different pine species. On some, such as white pine (Pinus strobus), the umbo sits right at the terminal point of the scale. On many other pines the umbo is actually on the dorsal (back) side of the scale. Umbos can range from small and rounded to large and pointy. Some umbos, like on the ponderosa pine (Pinus ponderosa) cone shown here, have sharp, prickly tips, which youíll definitely notice if you grab the cone with your bare hand!
Unless you have been living under a rock in your garden this past year, you are probably aware of a somewhat mysterious ailment that has been troubling honey bees lately. This problem has been coined Colony Collapse Disorder or CCD by researchers. This name seems to be somewhat of a placeholder however, as we still donít know exactly what the problem is.
Bee colonies that are afflicted with CCD have some tell-tale symptoms. Most of the adult population is gone from the hive, with no dead bees anywhere to be found around the hive. The brood (eggs, larvae, and pupae), young bees, the queen, along with honey and pollen stores, are still in the hive. Bees from other colonies will not rob any honey or pollen from these hives. This is a particularly strange phenomenon in beekeeping. Combs from these colonies cause healthy colonies to develop CCD symptoms.
This problem has set forth a large sampling effort done in part by a group formed to work on CCD, called the CCD working group. Throughout the past year they have been investigating this problem. One thing everyone seems to be in agreement upon is that this is not something being caused by any one factor. Genetic material collected and tested has found four pathogens associated with CCD colonies:
1. Israeli Acute Paralysis Virus
2. Acute Paralysis Virus
3. Nosema apis (a parastitic microsporidian
4. Nosema ceranae (a parastitic microsporidian)
The group has been careful to point out that these pathogens may be important markers in looking for CCD, but by themselves are not the cause of CCD. Other factors possibly contributing to CCD are environmental chemicals and stress to the bees caused by transportation for crop pollination and by parasitic mite loads.
The good news is that this year all pollination needs were met. In Minnesota, there has not been a reported case of CCD, and throughout the nation reports of failing bees have somewhat subsided. The biggest problem in Minnesota this summer was the dry weather affecting honey crops. Despite weather conditions, however, many beekeepers report having an average or slightly above average honey crop. Things seem to be buzzing along nicely throughout the industry thus far this fall. Beekeepers are being particularly mindful regarding their colonies this year and researchers have a great deal of new information to analyze. The collaboration between scientists and beekeepers makes this feel like a positive time to be involved with bees!
Live holiday plants are exceedingly popular and add a fresh and cheerful element to indoor seasonal displays. They are almost universally enjoyed and make great gifts throughout the holiday season for friends, relatives, shut-ins, co-workers, and hosts of the holiday parties we attend. Whether we lean towards the traditional (like poinsettias and Christmas cactus) or the out of the ordinary (maybe Christmas peppers and cyclamen), selecting healthy plants and following a few plant care basics will go a long way in extending the beauty of these holiday treasures.
Tips for selecting a healthy plant
Care of holiday plants in the home environment
Once holiday plants are brought home or to the office, place them in bright, indirect light and keep them moderately moist. Water thoroughly until water comes out of the bottom of the pot and allow the soil to dry out slightly between waterings. Many holiday plants come decorated in foil or plastic pot sleeves. Empty out excess water after each watering. In the past few years the advent of new dye types have made dyed poinsettias increasingly popular. White or cream colored poinsettias can be turned blue, orange, purple, or almost any other color desired. These new dyes do not shorten the bloom life like many of the dyes previously used. Avoid wetting dyed tissue because the color may run. Finally, avoid extreme changes in temperature and humidity as that may stress plants causing flowers and foliage to prematurely fall.
A few years ago I was invited to give a series of talks at various garden centers on basic concepts of plant physiology. During my presentation I showed some slides of pollarded ginkgo trees growing in Japan. For those of you who already know what pollarding means, Iím sure that you either love it or hate it! Briefly, pollarding is a pruning technique where a tree is dwarfed by continually pruning back the new growth at or near the branch tips every year or every few years. (See Photo 1)
Unlike the destructive practice of "topping", which removes branches indiscriminately at an arbitrary point in a vain effort to reduce a treeís crown, pollarding is a very labor-intensive and fairly biologically sound practice. After several years of pruning, the branches form knotty burls of callus tissue at their tips which produce thick masses of new growth. While this practice is quite common throughout Europe and much of developed Asia, most Americans arenít used to seeing it. When I suggested that we might try pollarding trees under utility lines to reduce their interference, more than a few audience members thought I was crazy! Interestingly, much of the same aesthetic and pruning techniques used in pollarding are used in other Eastern styles of tree pruning, especially the Japanese art of tree pruning, ueki no te ire, which is considered by most to be very beautiful.
There are many names for pruning styles in Asia. Some techniques are unique to a particular culture or country, while some appear to be common all over. My best advice is to use nature as your guide. In America, especially in the Midwest, we often prune trees for utilitarian purposes. Conversely, in the highly maintained gardens in much of Asia, trees become living sculpture, representing a view of nature that is sometimes unavailable in densely populated urban settings.
Most certainly, though, you donít have to travel overseas to find inspiration. Right here in Minnesota you can find inspiration in gnarled and twisted trees growing out of bluffs, pines growing on some rocky, windswept island in the Boundary Waters, or even the wild "open-grown" bur oaks found dotting the prairie remnants. Many of these trees have a growth habit reminiscent of Eastern pruning styles. In these cases, though, nature and the elements have been shaping these trees for decades. As home and landscape gardeners weíre looking for results a little sooner.
For now, letís take a "virtual tour" to check out some of the different styles of landscape tree pruning fairly common in Japan. The trees in Photos 2 and 3 are trained in a style that, when translated to English, means "traditional-shaped pine." There are several more specific types of pruning within this style that may produce a tree with a straight, curved, slanting, or "cascading" trunk style. Try searching online for landscape trees or bonsai for further inspiration.
Another common style of landscape pruning is called the globe style, shown in Photo 4. Many trees pruned in this style (often called "Hindu-Pan") are available for purchase at local garden centers and nurseries. Be aware that these trees arenít simply sheared like topiary to maintain the layered, globe effect. It often takes many years of time-consuming heading back or thinning cuts to achieve an attractive appearance. Even expensive nursery stock that looks good off the sales lot requires a lot of maintenance every year to keep up that appearance and good tree health.
Photos 5 and 6 show another common technique that trains a branch over a gate or outdoor entrance. This creates a living doorway into your home or garden, welcoming guests with greenery rather than just wood or metal. These trees are often pines or cypress, but could certainly be deciduous. Iíve certainly been impressed by wonderful old arbors and pergolas with grape, Boston ivy, or wisteria growing on them. Thereís no reason we canít train common, local tree species in this "branch-over-gate" style. Be open-minded and creative!
In contrast to other forms of Eastern-influenced horticulture like Japanese bonsai, or the Chinese art of potted landscapes called penjing, landscape trees in Asia are usually maintained only by pruning and training. It is extremely difficult, if not impossible, to restrict their root growth to promote dwarfing as is common in the above mentioned arts. In the landscape setting, gardeners and arborists use techniques like candle pinching in pines and heading back or thinning to lateral pruning cuts in both deciduous and coniferous species to promote a change in the growth habit. Branches and stems can also be bent or contorted using stakes, clamps, and rope. Many trees are supported semi-permanently to maintain a certain feel or look. Be sure to check out the resources listed at the end of this article for more specifics on training and pruning in these and other styles. For more inspiration visit the Japanese gardens at the University of Minnesota Landscape Arboretum in Chaska and the Marjorie McNeely Conservatory at Como Park in St. Paul. Many of the plant species growing in these gardens are native to the western hemisphere but are maintained and pruned in Eastern styles.
Here in Minnesota I often find arboricultural inspiration in urban or industrial areas (see Photos 7 and 8). Many of the trees growing there are under severe stress and are often "pruned" by passing trucks, machines, and road salt. While definitely not the best practices horticulturally, they still create an interesting effect that is reminiscent of those harsh, albeit more natural, landscapes!
Like most things in horticulture, there are a few rules that will allow for greater success when trying these Eastern pruning styles. If you already know how to prune trees using proper tools like bypass hand shears and pruning saws, youíre half-way there. Follow the recommended practices for making proper pruning cuts; donít start making flush-cuts because someone says thatís the "traditional way." We are always learning new things and sometimes the traditional way becomes the wrong way. Also, donít feel required to buy specialized pruning tools. If you already have good-quality pruning shears and/or saws you have just about everything you need. If you need practice in basic tree pruning, check out a book or visit any of the numerous online sites devoted to tree pruning. These skills are valuable to anyone pruning trees in any style, Eastern or Western.
Additionally, donít feel obligated to work with traditional Asian plant species or varieties; they may not grow well in our climate. Certain trees are often talked about in the old books and texts because thatís what was available at that time and in that part of the world. Use what you already have growing in your yard or garden. Stop by your local garden center or nursery and ask if they have any "reject stock". Some of those beat-up trees with double leaders or crooked stems might just be perfect for a particular project you have in mind.
Finally, I donít consider myself an expert in pollarding, bonsai, penjing, or any style of Eastern-influenced horticulture. I just like to goof around with little trees in pots and get a little creative with some of my landscape trees. Like Eric Mader states in his book, Ueki no Te Ire: The Art of Japanese Giant Bonsai, "[There are no] secret handshakes, blood oaths, or Ďspecial licensesí" required to prune your landscape trees in fun and interesting ways. In Japan most of the trees growing on private property are maintained by the home gardener or hobbyist. Experiment at first with "expendable" trees, look for inspiration in everyday landscapes, and develop your own style and aesthetic. Above all, donít get discouraged by failure; many mistakes made in the present can offer unique opportunities in the future!
Ueki no Te Ire: The Art of Japanese Giant Bonsai by Eric Mader
Available at www.giantbonsai.com
Niwaki: Pruning, Training and Shaping Japanese Garden Trees by Jake Hobson
Published by Timber Press: www.timberpress.com
Japanese Garden Journal
Online at: http://www.rothteien.com/
Pruning Shade Trees in Landscapes by Ed Gilman
Online at: http://hort.ifas.ufl.edu/woody/pruning/
We may not always appreciate the hard winters that Minnesota is known for but one advantage to this climate is that there are a number of arthropod pests that do not live here, including fire ants, Africanized honey bees (popularly referred to as killer bees), tarantulas and other types of spiders, certain species of cockroaches, and scorpions. However, that does not prevent some of these arthropods from occasionally being transported accidentally into Minnesota. While tropical and subtropical arthropods are not able to establish themselves this far north, they do surprise people when they show up. Ironically, at a time when people are starting to think about going south for the cold weather, the following invertebrates found their way north this November.
A scorpion was found in a factory in the Twin Cities. Dave Stone, the technician responsible for pest management at the facility, requested an identification. At about 1 1/2 inches long, this is an impressive looking scorpion. Because the factory receives material from across the country, it wasnít possible to determine the exact origination point for this scorpion. A picture of the specimen was sent to Texas A & M University where Dr. David Sissom examined it. He identified it as Centruroides gracilis, a species that only occurs in the U.S. in southern Florida. Dr. Sissom reported that the sting, while painful, was not dangerous. Dave Stone has kept the scorpion and is attempting to keep it alive in a terrarium.
A woman called the Entomology Department and said she had a large spider for anyone who was interested in it. She works in the produce department of a local grocery store and indicated that this spider was found on bananas shipped from Equador. The spider was brought to the St. Paul campus and was identified as a huntsman spider, Heteropoda venatoria, a type of giant crab spider. An impressive sized spider, its body is one inch long and it measures several inches across including the legs. You can recognize this spider by the way most of the spiderís legs point forward. This is also typical for crab spiders, family Thomisidae, which is a common group of spiders in Minnesota. This spider apparently had been injured as it only had seven legs when it was delivered. Huntsman spiders have been found in Minnesota a few times in the past and are usually found on bananas. It is not a dangerous spider, although it undoubtedly could bite if handled carelessly.
An unknown insect was discovered by a homeowner on celery she purchased at a local grocery store in Owatonna (Steele County). This insect was about 1/2 inch long with a reddish brown head and prothorax. The rest of the thorax, along with the legs, were yellowish with a dark brown stripe running down the middle of its back. The abdomen was also dark brown. It was particularly nasty-looking due to a pair of pinchers on the tip of its abdomen. This was quickly identified as an earwig, although not a species found in Minnesota. While the European earwig, Forficula auricularia, is present in this state, it is a reddish brown insect. The earwig found on the celery belongs to the genus Doru, an insect that is commonly found in the southern U.S. Despite the pinchers, this insect is harmless to people.
Some thoughtful person has given you an amaryllis this holiday season - - now what?! Whether you have received a beautiful blooming plant or a potted bulb, it will bloom without special treatment and brighten your home this winter. As a bonus, with a little nurturing and special care, particularly after they have finished blooming, the amaryllis bulb can provide you with beautiful flowers for several years to come.
Keep your amaryllis plant out of direct sunlight while it is in bloom. If you have a potted bulb, place it in a warm sunny spot until the flower buds show color; then move it out of direct sunlight. Cooler temperatures found in lower light locations will help them retain their blossoms longer. Amaryllis are sensitive to cold so donít place them where icy blasts from opened doors can hit them. After the flowers have faded, treat your amaryllis as a sun loving houseplant.
The secret of successfully growing amaryllis is to keep the plants actively growing after they finish blooming. After the flowers have faded, cut them off to prevent seed formation. You need not remove the flower stalk until it becomes yellow; in fact, it will help manufacture food for the bulb as long as it is green. Place the amaryllis plant in the brightest possible location indoors. Water it thoroughly, but allow it to become rather dry between waterings. Never water the plant when the soil is already moist because wet soil will promote bulb rot. You can group other sun loving houseplants around the amaryllis to hide its rather unattractive leaves. Keep it in the bright indoor location until it is warm enough to sink the pot in the soil outdoors. Place it in dappled sunlight at first and gradually move it to a brighter location where it will eventually have full sun for at least six hours daily. The leaves may develop some reddish scorch spots, but the leaves will come off in the fall anyway. Fertilize with a balanced houseplant fertilizer monthly to build up nutrients for blooming next year.
The amaryllis should be brought indoors before the first frost in the fall. Store the pots in a dark place such as a basement or cool closet and do not water. Remove the leaves after they have become brown and shriveled. The bulb may be forced into bloom again after resting about eight to twelve weeks. Inspect the bulbs periodically and bring them into light if new growth begins to appear. If not, you can force new growth by watering the soil thoroughly and placing the amaryllis back into a sunny location. Usually one or more flower stalks appear first, but occasionally they are preceded by leaves.
Amaryllis plants bloom best when they are pot-bound so they will need repotting only every three or four years. The best time to repot them is after they have gone through a dormant period. Plant the bulb in a pot that is an inch or so larger than the diameter of the bulb and has drainage holes in the bottom. Use a potting mixture that drains well and place the bulb so that the upper half is above the surface of the medium. Immediately after planting, thoroughly water the bulb and then continue watering whenever the potting mixture feels dry to the touch. Do not fertilize the bulb until after the plant begins to grow; then it is essential that it is fertilized regularly.
If the bulb does not produce a flower stalk, it has not stored enough nutrients during the post-blooming period. It is very important that they receive plenty of bright sunlight after they have finished blooming. They require some care and attention throughout the year, but those beautiful clusters of eight- to ten-inch trumpet shaped flowers are a great reward for your diligence.
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Regional Extension Educator - Horticulture