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recycling or putting plants up for adoption

Do you know of a website or referral service for “recycling” plants? I have about 10 feet of barberry (Berberis) bushes that I want to get rid of and thought if they could be dug up with enough of the roots, someone could use them. They are quite ornamental, birds love them, and the thorns are quite lethal (for me, not the birds).

You can contact Plant Amnesty’s Adopt-a-Plant program.
You can also try GardenWeb’s Pacific Northwest Garden Exchange, or freecycle. You might also see if there is a “Buy Nothing” group in your area which you can join.

flower arrangement tips

What is the right proportion of cut flowers to create a nice arrangement in a vase? Can you give me some other suggestions about flower arranging?

This Brooklyn Botanic Garden article, provides some helpful tips on different aspects of flower arrangement. Here is an excerpt from Cut Flower Care by Rose Edinger:
“The height of the flowers should be in proportion to the size of the container—that is, the height of the flowers should not exceed one and a half times the height of the container.”

The Miller Library also has many books about flower arranging, two of which I’ve listed below:

Flower Arranging from the Garden (1989), by Daphne and Sid Love
The Complete Guide to Flower Arranging (1995), by Jane Packer

common pests and diseases affecting Japanese maples

I have a lovely, 3-ft. Japanese Maple (Acer palmatum) that has access to full sun. I am guessing it is over 3 years old at least. The tree is leafing beautifully, but last week I noticed there are “pustules” all over the stems and branches. They are yellowish-brown in color and somewhat mottled looking. They form in irregular clusters along the branch. Each pustule is about the size of a ladybug; in fact, at first I thought they were beetles, but they do not move and when I removed one, it was liquid-y inside and left a thin, white streak along the branch. I am a beginner homeowner, so I do not know what this is. Do you have any ideas? What can I do to treat this? I would hate to lose my Japanese Maple.

The best way to determine if your tree is diseased is to bring a sample to a Master Gardener Diagnostic Clinic and ask a Master Gardener to diagnose it for you. This service is free to home gardeners.

What you describe sounds like several quite different problems (canker, or scale, for instance), which is why having a hands-on diagnosis is so important. Below is general information about maple diseases which you can compare with your tree. Additionally, I recommend the book Japanese Maples by J.D. Vertrees and Peter Gregory (Timber Press, 2009). It has sections on the most common pests and diseases affecting Japanese maples.

This page from the University of California Agriculture and Resources about Maples includes an extensive list of diseases and disorders that affect maple trees.

Clemson State University has a factsheet on Maple diseases and insect pests (read the entry on scale).

Try searching for “maple” in Pacific Northwest Guide to Plant Disease Control, and compare the descriptions to see if any ring true with what you are seeing. Ultimately, though, the best thing is to get a hands-on diagnosis from the Master Gardeners, as mentioned above.

grafting a walnut scion onto a maple

Is it possible to graft a walnut scion onto a maple tree?

The book, Plant Propagation edited by Alan Toogood (American Horticultural Society/DK Publishing 1999) says that Juglans regia and Juglans nigra, grown for their edible nuts, are usually whip-and-tongue grafted. You would “use a slightly narrower scion than the stock so the thinner scion bark will align with the stock’s cambium more easily.”

I was not able to find any information on grafting a walnut scion onto a maple, but here is an article (pdf) on by William Reid, which has detailed information.

This publication from the University of Georgia College of Agricultural & Environmental Sciences, entitled “Propagating deciduous fruit plants common to Georgia” (1999) indicates that whip grafting or ring budding will work best for walnuts.

Philadelphus lewisii habitat and care

What is the specific habitat of the Philadelphus lewisii (wild mock orange)?

What does this plant need from the habitat in order to survive?

What range does the Philadelphus lewisii grow in?

What family is it in?

What other plants does it often grow around?

What specific habitat does it need?

Where does it grow?

Is it an annual or a perennial plant?

Philadelphus lewisii is a Northwest native, a common shrub east and west of the Cascades. According to Trees and Shrubs for Pacific Northwest Gardens, 2nd edition by John A. Grant and Carol L. Grant, it will “thrive in almost any garden soil in either full sun or partial shade, and are of the easiest possible culture. The hybrids respond noticeably to generous cultivation , fertilizer, and water. (It belongs to) the group of summer-flowering shrubs that are best pruned immediately after flowering.\”

Philadelphus lewisii is a deciduous shrub (in other words, it is not an annual and, although it has a long life span, it is not like an herbaceous perennial that completes its life cycle and starts over the next spring–it is a woody deciduous plant which loses its leaves in winter). (Source: The Royal Horticultural Society A-Z Encyclopedia of Garden Plants, edited by Christopher Brickell; Dorling Kindersley, 1996).

Here is a link to a page from the Washington Native Plant Society about Philadelphus lewisii and its habitat.

It is a Northwest native (state flower of Idaho), and grows throughout Western North America (from British Columbia south to Oregon), southern Europe, and eastern Asia.

The genus Philadelphus grows in rocky woods, semi-desert, and open areas in wet forest. In gardens, it prefers loamy soil and moderate sun.

The genus Philadelphus belongs to the Hydrangeaceae family.

shrubs or trees that provide privacy screens

What shrubs or trees will grow quickly to provide a privacy screen above the 6 foot fence between me and my neighbor? My back yard is only about 20 feet from house to fence, and the first 10 feet is a concrete patio.

The classic fast-growing evergreens for hedges are Thuja ‘Green Giant’ or Leyland cypress (x Cupressocyparis leylandii), but they are a bit boring and because they grow so fast (1-3 ft/yr) it can be a big chore to keep them at a reasonable height. These trees do not stop at 8 feet, but could get to 30-50 feet.

Another fast evergreen is Pyracantha (Pyracantha crenatoserrata to ~8 feet). It is a shrub, but is easily trained/pruned to grow flat. In the past Forestfarm nursery in Oregon has sold both of these, as do most large nurseries. Be aware, however, that this shrub has fierce thorns!

Various types of bamboo could be an option for a fast screen, but plants may be expensive and running bamboo species MUST have a root barrier installed.

amending clay soils

I have very bad rocky, clay soil. To dig in this is like prison work. We rototilled the area and put in topsoil and now it is like quicksand. I am going to build up my beds but want to break some up to get trees and other plants to take root. What are you supposed to use or do with hard clay? I love plants, and would like to get gardening, but I can’t think of how to solve this problem.

There is no immediate solution. It may take a few years of adding good amounts of organic matter and compost to improve the soil quality. Here is some information that may help you along the way.

A Seattle Post-Intelligencer article, ‘The well-made bed: Pile on the compost’ by Ann Lovejoy, provides some tips for improving your soil with compost.

Washington State University Extension horticulture professor Linda Chalker-Scott has a cautionary tale on how NOT to amend clay soil, plus tips on improving it slowly over time.

Fine Gardening has an online article on improving clay soil.

Lastly, a Home and Garden Television article entitled, “How to plant in rocky soil” may help you overcome the rockiness of your yard.

planting for slope stabilization

I live in a condo. The conifers on the site are beginning to obstruct the view of the neighbors. Our covenant with these neighbors says trees must not exceed a height of 25 feet. Last year several of the conifers were topped and others removed. Our concern now is that we may have to either top or remove more trees. We don’t want to block the neighbors’ view but we also don’t want to destabilize the ground – we all live on a hillside. What can we do over the next 5, 10, 15, 20 years to decrease the number of conifers and replace them with other trees that will be neighbor-friendly and keep our hill stable?

The short answer is to plant shrubs and groundcovers.

The long answer is that slope stabilization is a serious concern and deserves expert advice. Get started in your research by reading the articles produced by the Washington Department of Ecology:

Slope Stabilization and Control Using Vegetation.

Your condo association may want to hire a consulting arborist and/or a civil engineer (“To locate technical experts such as experienced registered engineers specializing in geotechnical and/or drainage projects, use local telephone directories or call the Seattle or Kitsap branch of the American Society of Civil Engineers (ASCE) for membership references.” from DOE site)

For an arborist referral try:

Plant Amnesty

The Pacific Northwest chapter of the International Society of Arboriculture has information about hiring an arborist.

The International Society of Arboriculture can also help to narrow the search to your area.

broom plant used in Japanese flower arrangement

While living in Japan and practicing flower arrangement, I often used a branch known as ossified broom. It was always available at flower stores there. The color is gray-green, has the typical multiple straight stems as Scotch Broom but also had some thick and twisted branches that are very attractive in arrangements. I would like to plant it so that I would have a ready supply. Can you help me find the correct name?

I consulted a number of books on Japanese flower arrangement, including The Art of Arranging Flowers: A Complete Guide to Japanese Ikebana, by Shozo Sato (Harry N. Abrams, 1965). ‘Broom’ may be the common name of a number of different plants, such as Spanish broom (Spartium junceum), Scotch broom (Cytisus scoparius), and broom cypress (Kochia scoparia). Unfortunately, these plants are considered noxious weeds in the State of Washington.

You may want to consider a type of broom (Genista or Cytisus) that is not considered invasive.

From your description of the branches, I wonder if the appearance would be similar to
Corylus avellana ‘Contorta’ (Henry Lauder’s walking stick).

plants for restoring wetlands

I am an Ecologist with Adopt-A-Stream Foundation, a non-profit stream restoration organization. I am creating a planting plan for a golf course in Snohomish County. My constraints: Low-growing native shrubs with extensive root systems to help filter out the golf course irrigation water before it enters the stream. Willow would be an obvious choice, but it would grow too tall and out of control. I was looking at such species as Snowberry (Symphoricarpos), Nootka Rose (Rosa nutkana), Salmonberry (Rubus spectabilis), etc. It would have to be a FAC+ (streams and wetlands). Any thoughts?

FAC+ is a wetland indicator status term meaning “Facultative,” i.e., more likely to occur in wetlands but also found in non-wetlands.

I found a list in Restoring Wetlands in Washington Publ#93-17 and picked out the FAC-identified ones, eliminating all the tall trees and shrubs. Symphoricarpos (Snowberry) would be a good option, but Rosa nutkana (Nootka Rose) and Rubus spectabilis (Salmonberry) get too big for your purposes. A different rose I could recommend is Rosa gymnocarpa (Baldhip Rose). Many of the following recommendations are grasses of one sort or another. (See the USDA Wetland Indicator status definitions.)

Allium geyeri (non-native) FACU

Athyrium filix femina FAC

Carex aperta (non-native) FACW

Carex stipata FACW

Deschampsia caespitosa FACW

Juncus effusus and ensifolius FACW

Ledum glandulosum FACW

Sambucus racemosa var. melanocarpa FACU

Spirea douglasii FACW

You might also try the Snohomish County Conservation District website.