lawns and dog urine damage

What can I do to repair the unsightly patches left in my lawn by the neighbor’s dog, which urinates there daily? Should I reseed or patch with sod?

First of all, if the dog’s person cannot encourage it to ‘go’ elsewhere, this will be a perpetual issue. That makes me think that it’s best to take the easiest route, which is to saturate the spots on the lawn as soon as you notice the dog has been there. A University of California, Davis publication entitled “Lawns ‘n’ Dogs” suggests prevention by flooding the small area where the dog has urinated as soon as possible after the event–keep a watering can at the ready! They recommend that you only repair the lawn if the grass is significantly burned, covers a large area, and is a cool-season non-creeping grass variety–other types of grass will regrow on their own quite easily.

Colorado State University’s Garden Notes published an article entitled “Dog Urine Damage on Lawns: Cause, Cure and Prevention.”
Excerpt:
“If the affected spots are brown, (the turf may or may not be dead):

Increase irrigation amount and/or frequency to help dilute salts that have accumulated in the soil. This may help still-living turf recover, and will dilute salts in those areas where the turf has been killed (allowing for more effective re-seeding).
When turf has been killed, the dead sod and some soil (0.5-1 inch of soil) can be removed. Re-sod the area with new grass.
Individual dead/damaged spots can be re-seeded as follows:In a Kentucky bluegrass lawn: Spot seed with Kentucky bluegrass (marginally effective) or perennial ryegrass (more effective). Tall fescue, K31 tall fescue, dwarf fescue, or annual (Italian) ryegrass should NOT be used for spot-seeding a bluegrass lawn.
In a tall fescue lawn:Spot seed with turf-type tall fescue (sometimes called dwarf fescue). Perennial ryegrass can also be used, but it has a finer texture and the newly seeded spots will look different from the rest of the lawn. Do NOT use K31 fescue or annual (Italian) ryegrass for spot-seeding a tall fescue lawn.
Fine fescue lawns: Seed with fine fescue seed. The use of perennial ryegrass or tall fescue is NOT recommended, as the spots will have a different color, texture, and growth rate.
Zoysiagrass and bermudagrass lawns: Patch using sod from a sod farm, or by transplanting sod from an inconspicuous area of same the lawn.”

David McDonald’s guide, Ecologically Sound Lawn Care for the Pacific Northwest, has recommendations on the best grass varieties to use in our area:

“For conventional lawns west of the Cascade Mountains (the region covered by this report), most turf professionals say that mixtures of turf-type perennial ryegrasses and the fine fescues (such as chewings, creeping red and hard fescue) offer the greatest flexibility and adaptability to local conditions. A mixture of species and varieties will withstand diseases and adapt to various sites much better than a monoculture.
“In general, ryegrasses like full sun, whereas the fescues do well in sun (and are more drought tolerant) but are also among the most shade-tolerant of Northwest-adapted species. Ryegrass stands up best to heavy wear, much better than fescues, so it is the choice for sports fields. But most ryegrasses have a higher nitrogen requirement than the fescues, and so are is less appropriate for low maintenance turf. Seeding a blend of several species and varieties will allow each to thrive in the lawn area that suits it best.”

management solutions to cutworms

I have grey-green fairly large caterpillars eating my foxgloves. They are eating them to shreds but I have hopes that they will still flower. They are leaving what looks like rodent droppings in the leaves. They are eating only the foxgloves. My question is what are they and is it okay to keep the plants or should I pull them up?

I strongly suspect you have variegated (or climbing) cutworms. I have these nasty bugs too and can give you a long list of plants they eat. Foxgloves are their favorite. Here are some management solutions in order of most work, least toxic to less work, but more toxic:

1) hand-pick after dark (with a flashlight) starting in January and continuing through May.
2) spray Bt (Bacillus thuringiensis) (found in Caterpillar Killer). It must be reapplied after rain. Be careful where you spray it because it will also kill butterfly caterpillars.
3) general pesticides will kill cutworms and many other critters that come along, including bees and may harm birds.

Here are some links to more information:
U.C. Davis Integrated Pest Management
Oregon State University Department of Horticulture

Managing leaf gall on Arctostaphylos uva-ursi

My Arctostaphylos uva-ursi has suffered from galls caused by aphids. What approach would be best to combat the aphids and when is the best time in their life cycle to attack?

Kinnikinnick or Arctostaphylos uva-ursi sometimes suffers from galls caused by aphids, and is also susceptible to fungal diseases. If your plant has galls, you would see distorted, thickened, and often reddish leaves which almost don’t seem leaf-like. The aphids may also secrete honeydew which can then turn blackish with mold.

Douglas Justice, University of British Columbia Botanical Garden Associate Director offers these comments on Arctostaphylos uva-ursi:

The Arctostaphylos uva-ursi cultivar ‘Vancouver Jade’ — a UBC introduction and one of the most widely grown cultivars in temperate climates — is adapted to wetter conditions than many other cultivars, as it was selected from the Pacific Northwest. Nevertheless, like all kinnikinnicks, it is not a plant for poorly drained, shaded or high traffic areas. And unfortunately, it appears to be rather more susceptible to manzanita pod gall aphid than other cultivars. Populations of that insect pest can build up during “warm winter” periods (such as we’ve been experiencing in Vancouver over the past several years) and disfigure plants significantly.
Source: UBC Botanical Garden Forums

Oregon State University has information about leaf gall on Arctostaphylos uva-ursi in their Plant Disease management handbook online.

The following, from Pacific Northwest Insect Management Handbook (WSU, OSU and U. of Idaho, 2005) provides more information about the aphids.

Kinnikinnick Arctostaphylos – Aphids

Manzanita leafgall aphid, Tamalia coweni:

Pest description and crop damage – Manzanita leafgall aphids are grayish or greenish in color and prefer new growth. They feed on the leaves of kinnikinnick and other manzanita species (Arctostaphylos spp.). Aphid feeding causes the leaves to thicken and form bright red galls. Older galls turn brown. Severe infestations may slow the growth of the plant.

Nongall-forming aphids also may be seen occasionally on kinnikinnick. They are greenish, soft-bodied insects that may feed on leaves or stems. Honeydew, a sweet, sticky material, may be associated with aphid feeding. It may attract ants or become covered with a growth of dark, sooty mold. Severe infestations may result in leaf and twig dieback.

Management-biological control:
Syrphid fly larvae are important predators of leafgall aphids, and will feed on them inside the galls. Avoid use of broad-spectrum insecticides which kill these and other beneficial insects such as ladybird beetles and parasitic wasps.

Management-cultural control:
Prune off and destroy galls where seen. Avoid frequent shearing and overfertilization, which encourages succulent new growth favored by aphids. Wash other aphid pests from plants with a strong stream of water or by hand-wiping. Avoid excessive watering, and use slow-release or organic sources of nitrogen. Control ants, which “farm” aphids and protect them from predators in order to harvest their honeydew.

more about Lysimachia punctata ‘Alexander’

I bought a Lysimachia punctata ‘Alexander’ (variegated) at a plant sale last weekend. I can’t find anything about it in my books. Can you tell me more about it? How tall, invasive or not, best place to plant, anything else you think I should know.

I found information on the website of a local gardener, Paghat, with a detailed description of this form of loosestrife. Although it is not supposed to be as aggressive as the species (L. punctata) or as invasive as L. vulgaris (a noxious weed in King County), I recommend keeping an eye on it. Paghat says:
“‘Alexander’ has variegated leaves, sage-green with cream borders, and sunny yellow flowers. It purports to be a more restrained version of a flower that in the species form is notoriously invasive and often too aggressive for neighboring perennials. Even ‘Alexander,’ though comparatively slow growing, eventually becomes a large two-foot by two-foot clump with a big root system that can threaten nearby delicate flowers, so take care what you plant around it.”

conditioning clay and heavy soils

Help! My clay soil is stunting the growth of my plants. I’ve amended the soil with compost and manure. Is there a another method of conditioning the soil that you can recommend?

First and most important, it appears mulching is the best organic solution for conditioning clay and heavy soils. Organic soil conditioners include compost, well-rotted animal manures, and natural fertilizers. Planting green manures such as clover, rye grass, or vetch are also effective for breaking up large clods in clay soil over time.

Sheet composting – laying compost over the entire area to be worked and using a fork (or rototiller) to work it into the soil to a depth of 2-4 inches – is cited by the resources listed below as an efficient method of soil conditioning. Both books listed below recommend repeating this process at least twice a year, in early spring and in late fall.

Secrets to Great Soil [by Elizabeth P. Stell, 1998, (pbk)] and

The Gardener’s Guide to Better Soil [by Gene Logsdon, 1975, (pbk)]

The Saving Water Partnership (the City of Seattle and other government entities) has a website full of information about improving soil.

The site includes Growing Healthy Soil.

Current thinking contradicts the notion of working compost or other amendments into the soil, as explained in a March 31, 2010 Garden Professors blog post by Professor Linda Chalker-Scott of Washington State University Extension Horticulture. She specifically takes issue with the “Growing Healthy Soil” information linked above. Here is an excerpt:
“Not only will extensive digging or rototilling destroy any soil structure you might have, it will also take out the roots of any desirable plants in the vicinity). […] improper soil amendment can cause serious problems such as soil subsidence, perched water tables, and nutrient overloads. This last point is especially important to anyone living near aquatic ecosystems, since excess nutrients always end up in the water.
Before you plant this year, find out what your soil needs before amending it. And remember that mulching is the natural (and sustainable) way to add organic matter to the soil.”

list of purple beech cultivars

Can you give me a list of purple beech cultivars?

There are several Fagus sylvatica varieties with purple foliage:

‘Atropunicea’ (copper beech, purple beech) alt. ‘Riversii’ or ‘Purpurea’ – 50-60 feet tall, 35-45 feet wide; good in containers

‘Dawyck Purple’ – columnar to 70 feet tall and 15 feet wide

‘Purpurea Pendula’ (weeping copper beech) – usu. no more than 10 feet tall and wide; good in containers

‘Red Obelisk’ – columnar

Source: Western Garden Book, Sunset Publishing Corporation, 7th edition, 2001, p.347.

And from Paghat, the website of a Seattle area gardener:
F.sylvatica ‘Black Swan’ – swan neck growth habit
F.sylvatica ‘Rohani’

caring for Dendrobium orchids

I have a couple of Dendrobium orchids, and one other that I don’t know the name of. Both the Dendrobium have lost all their leaves, and I’m worried that they will die if they are not repotted soon. There is white fuzzy mold growing in the potting mix (which is just bark) of at least one of them, and I researched a little online and found that it is a common kind of snow white fungus (that may not be the right name) that is common to orchids in general.

I’m worried about root rot, and I’m wondering what I can do to try to revive these two orchids back to blooming. I read that soaking the roots in hydrogen peroxide can often help kill the fungus and then repotting thereafter can possibly revive them. What would you suggest for a repotting mix, and do you have any tips on reviving orchids once that have lost all their leaves?

The roots seem to still be intact, and do not appear to be rotted, as far as I can tell. I’m also wondering about good types of greenhouses/shelters to keep them in, as well as heaters to keep them a little warmer in the house — they seem to be having a harder time with the 60 degree temperatures that my apartment tends to be. Any advice you could give would be great!

Some Dendrobium are deciduous, so your plants are likely acting exactly as they should. However, now that they’ve lost their leaves, you should restrict watering them through the winter, watering them only enough to keep them from shriveling, until flower buds form. Then, resume watering again. The species of Dendrobium that are deciduous require night temps of 50-55 degrees F during the winter.

Dendrobium grow well in Osmunda fiber, a potting medium, or bark if they are carefully staked, though they shouldn’t be re-potted or divided until new growth starts. Also, Dendrobium with 4 or 5 shoots will grow well in a 4-5 inch pot, so you don’t necessarily need to increase the pot size when you do re-pot your plants.

If you cut back on the water you give your Dendrobium through the winter, you shouldn’t have to worry about root rot/fungi, especially if you repot them when new growth appears.

The advice above is taken from Home Orchid Growing (by Rebecca T. Northen, 1990, pp. 209-212).

Orchid Growing Basics (by G. Schoser, 1993, pp.40-45) shows some ways you can create a good place for orchids inside your home. For Dendrobium, placing the plants in a window with southern exposure, a grow light that will give them 12 hours of light each day, and humidity (Schoser recommends standing the pots on upsidedown flower pots in a tray of water) seem to be the most important considerations.

The Miller Library has many, many books on orchid growing.

Also, you might want to investigate the Northwest Orchid Society.

shrubs and trees to view from below

Are there any lists of shrubs/small trees that are best viewed from below, such as Styrax or Halesia?

While there are no lists of shrubs/small trees best viewed from below, there is a list of trees with weeping habits in The Pacific Northwest Gardener’s Book of Lists (Ray and Jan McNeilan, 1997). Many genera of conifers – Cedrus (cedar), Chamaecyparis (cypress), Larix (larch), Picea (spruce), Pinus (pine), and Tsuga (hemlock) – have weeping forms, often indicated by a variety name ‘Pendula’ or ‘Pendulum’. There are weeping birches (Betula), beeches (Fagus), and cherries (Prunus), too.

You are correct about Styrax and Halesia. Additionally, I ran across a few individual species that may be of interest to you as I researched this question:
–Davidia involucrata
–Laburnum anagyroides
–flowering currants, Ribes spp.
–flowering cherry trees, particularly Prunus padus
–various plants in the Ericaceae family have bell-shaped flowers that hang on the underside of the stem.

I would add that any tree which has a naturally graceful branching pattern and/or delicately shaped foliage (such as Japanese maples) would be pleasant to view from below, as well as from other angles.

fast growing and deciduous trees that do well in the sun

We are looking for a tree to plant in our backyard to provide some shade. We live in a location that gets lots of sun. We want something that will grow quickly, develop a canopy that we can walk under, will get approximately 20-30 feet tall, 15-20 feet wide, and not need a lot of water. Evergreen is probably out of the question. Any suggestions?

I think that your best bet may be a maple. Three maple species surfaced that meet your criteria of a quick growing, 20-30 feet tall tree with an equal or greater spread, that will do well in the sun.

—Acer circinatum, the vine maple (the only downside–this may be a bit shrubby for your landscape)
—Acer ginnala, the Amur maple
—Acer palmatum, the Japanese maple (you\’ll need to be choosy in order to find a cultivar that will reach 20-30 feet, but there are some that do. Additionally, A. palmatum will tolerate drier soils than A. circinatum.)

Sources:
The Pacific Northwest Gardener\’s Book of Lists , R. & J. McNeilan, 1997, p. 18, 27, 30.
Tree & Shrub Gardening for Washington and Oregon , A. Beck & M. Binetti, 2001, p. 244-249.
Trees & Shrubs for Northwest Gardens , J. A. Grant & C. L. Grant, 1990, p. 56-58.

organic controls for wireworms

Our community vegetable garden has been overrun with wireworms this year. Is there anything we can do to control them?

Here are the links I’ve located which mention some organic controls for wireworms:
Vancouver Sun article by Randy Shore on organic managmenet of wireworm and root maggot. Wireworm Biology and Nonchemical Management in Potatoes in the Pacific Northwest (specific to potato crops in the Pacific Northwest, but includes useful information that shows the science to back up suggestions in the previous link)

As you might expect, organic methods are not the toxic silver-bullet approach to pest management–they are longer range. You might have community gardeners plant their crops in containers for the time being (or maybe someone would be willing to donate raised beds?).

I consulted Backyard Bounty: The Complete Guide to Year-Round Organic Gardening in the Pacific Northwest by Linda Gilkeson (New Society Publishers, 2011). Here’s a summary of what she says:

Check the soil for the eggs of adult beetles in April and May.
“Wireworms can be especially damaging for the first few years after new sod is turned for a garden.”
Larvae take 3-6 years to develop into adults. The worst damage is in spring and fall when they feed close to the soil surface. In summer and winter, they burrow deeper–but they also do this when there is nothing to eat. As you have already noticed, they are attracted to plant roots.
Planting late avoids some wireworms. The author recommends not planting fall rye as a cover crop, as it attracts adults to lay eggs there. “Instead of cover crops, I prefer to keep empty garden beds weed-free all winter and use compost and leaf mold to add organic matter. Sow extra seeds of peas, beans and corn to allow for losses. Lightly fork over the soil in annual beds several times before planting and pick out wireworms; their light color makes them easy to see against the soil.”
She suggests removing all weeds and roots from the bed. Then, use chunks of potato and carrot as bait, skewering each chunk on a short stick (to serve as a marker) and bury the pieces a few inches deep in the soil. Pull up the wireworm traps every day or two and destroy the worms. “For heavily infested soil. it might be worth trying ‘trap crops.’ Starting with bare soil, about 10 days before you want to plant the bed, sow rows of wheat or barley (about four seeds per inch) about a yard apart. The germinating seeds attract the wireworms if there are no other roots in the soil. After 10 days, pull the grain seedlings and destroy any wireworms found in the soil along the row and among the roots.”
About parasitic (beneficial) nematodes, she says that the only species that has shown some effectiveness against wireworms is Heterorhabditis bacteriaphora.