What is the lifespan of our native sword fern?
The native sword fern, Polystichum munitum, is discussed in local author Sue Olsen’s Encyclopedia of Garden Ferns (Timber Press, 2007). She does not mention the plant’s lifespan except to say that it will suffer and decline with excessive summer heat and humidity (more common in eastern and southern U.S.), and sometimes with long periods of freezing temperatures as well.
Sword fern has a reputation as a tough, long-lived perennial (i.e., returning year after year), and it readily self-propagates from spores, but I have not found any resources which mention the average duration of an individual plant. Most will survive in the Pacific Northwest for many years.
Are azaleas poisonous to cats?
Azaleas are indeed a problem for cats and other pets. See this link from Purdue University’s Veterinary Program.
Excerpt:
“These ornamental shrubs aren’t commonly nibbled on but they can cause fatal heart problems in dogs, cats, and pet birds. Signs to watch for are similar to that of the yews and include weakness, fainting, salivation, difficulty breathing, vomiting, and diarrhea.”
According to the Handbook of Poisonous and Injurious Plants, 2nd ed., by Lewis Nelson et al. (New York Botanical Garden/Springer, 2007), all Rhododendron species, including Azaleas, contain grayanotoxins in their leaves. Honey made from the flower nectar would also be toxic.
I am a professional landscaper in the Portland area. I am wondering if Betula jacquemontii have much of a problem with aphids or other pests. Everything I read says they do, but since this tree is one of the Great Plant Picks, I wonder if that’s not the case.
There is certainly the potential for aphids with this type of birch. I don’t think all the plants listed in Great Plant Picks are necessarily immune to problems, more that they can serve a particular purpose in the landscape. Betula utilis var. jacquemontii is also susceptible to bronze birch borer, according to Oregon State University.
University of British Columbia Botanical Garden Forums includes a discussion of the merits (or not) of this tree, including this comment from Seattle-area gardening expert Ron Brightman:
“Silver birch is customarily Betula pendula. It grows large and is an aphid magnet in my area. Betula utilis jacquemontii does not produce the same elegant weeping habit. But the clone commonly sold here displays stark white bark. Mine became infested with what looked to be the same leaf miner that can be quite abundant on native stands of B. papyrifera north of here. Finding the effects of the miners tiresome and this not being a rare tree here, I cut it down. Since native paper birch trees are abundant around Vancouver I would wonder if you might end up with the same problem.”
Here’s another link of interest, from Washington State University. It mentions that “this tree is susceptible to bronze birch borer, a wood boring beetle that will girdle the trunk. Aphids can be problem on the foliage. Excrement from aphid feeding can leave the ground sticky beneath this tree.”
Jacquemontii birch is common as a street tree in Seattle, and as the neighbor of a row of three of these birches, I can say that so far they appear relatively pest-free (I’ve seen a hint or two of sticky aphid honeydew on the leaves ), but they make voluminous leaf and bark litter which blows into my garden. I keep thinking the bark is wastepaper (grocery receipts, etc.). It looks great on the trees, but is a minor nuisance when blown far and wide.
Could you tell me more about a new type of fruit fly that is supposedly infesting fruit here in the Pacific Northwest? Which fruit are affected?
The fruit fly is called the Spotted Wing Drosophila. It is known to affect strawberry, raspberry, blueberry, plum, peach, cherry, and grape. Oregon State University has created an information clearinghouse about this pest. Here is their information for home fruit growers. Washington State University has also devoted several web pages to this fly. Here is their Integrated Pest Management information, excerpted below (SWD stands for Spotted Wing Drosophila):
“Monitor for SWD using traps. […] These vinegar traps are for monitoring purposes only and will not provide control of SWD. Remember, chemical control is not necessary if SWD is not present.
Composting fruit will likely not be effective at destroying maggots and pupae.
Remove infested and fallen fruit. Destroy or dispose of infested fruit in a sealed container.
Management recommendations are currently being developed for this pest. For the time being, good sanitation practices should be used.”
Whatcom County Extension has clear, basic information for home gardeners as well. Since this insect is a relatively recent invader in the Northwest, information is constantly being adjusted and research is ongoing.
I’ve been noticing creatures in my garden pond that I’m hoping are not mosquito larvae. How can I tell the difference between mosquitoes and tadpoles? I wouldn’t mind having frogs, but I don’t want to breed mosquitoes!
The following may help you tell the difference between mosquito larvae and tadpoles.
Mosquito (note their hairy appearance):
New South Wales Mosquito Monitoring image 1
Tadpole (note their smooth sides):
University of Richmond biology professor W. John Hayden’s photos
If you are concerned about mosquitoes in your pond, there are a number of preventive steps you can take. Mosquitoes are less likely to thrive in moving water, so you may want to install a submersible pump. Washington State University Extension provides information for homeowners on West Nile virus prevention and mosquito control. Here is an excerpt:
“Manage weeds; keep vegetation short around water. Adult mosquitoes are attracted to dense, tall vegetation around water.
Remove unnecessary floating structures or debris from ponds. Mosquitoes are often found around floating debris.
Keep drains, ditches and culverts clean to allow proper drainage.
Consider stocking ornamental or permanent, self-contained ponds with insect-eating fish, such as goldfish.
Shape pond edges to a shelf or steep slope. Mosquitoes prefer shallow pond edges.”
Can I graft an Asian pear onto Anjou rootstock?
Anjou is a European pear variety, and European pears are the species Pyrus communis, which is not an acceptable rootstock for Asian pears, according to a Pacific Northwest Extension publication by Robert Stebbins on “Choosing Pear Rootstocks for the Pacific Northwest.” Here is an excerpt:
“Asian pear trees require rootstocks that impart a high state of vigor. No Pyrus communis rootstocks are vigorous enough for most Asian pears, with the possible exception of the most vigorous Old Home x Farmingdale clones.
Asian pears require vigorous rootstocks such as P. betulaefolia or P. calleryana. Unfortunately, their cold-hardiness isn’t well-known.”
I have a client whose Clematis I just renovated. The client called to say the ends of the cut stems were frothing! What could be causing this?
My best guess (and it is only a guess, since I am basing it solely on your description) is that it could be slime flux. According to the Royal Horticultural Society, “pruned stems may fail to reshoot and ooze a sticky substance–this is known as slime flux.” To confirm this theory, ask the client if the frothy ooze was pinkish orange in hue, and if it had an unpleasant odor. Here is more about this problem from the Daily Telegraph’s garden advice column by Helen Yemm excerpted below:
“This is not so much a disease as a condition that affects some trees and shrubs in spring. Bacteria enter the plant through cracks in the stem – which may well be caused by a combination of adverse weather conditions – and then attack the sap as the plant springs into action early in the year.
Slime flux is often fatal but it depends where the damage is. Everything above the oozing wound will certainly die and should be cut down. However, the plant may well shoot out from below and recover.
Slime flux will not spread to other plants as diseases do, nor will it contaminate the soil like clematis wilt. However, its occurrence would indicate that, for some reason, the general growing conditions in that part of the garden have become unsuitable. If you do lose your clematis, then perhaps it would be a better idea to plant a new one in a less exposed spot.”
I have grown primroses both in Seattle and in South Everett. The first time the plants looked like the leaves were being eaten, and then when I pulled one of the almost-eaten plants out of the pot, most of the roots were gone. When I cleaned out the pot, I found many little white grubs in the dirt. It happened again in my new location. I am mystified, as I grow them in pots on a second floor balcony. What could be causing this and is there a way to grow primroses without this happening?
I wonder if the problem is in the potting soil. Were you using the same batch each time? It might be worth experimenting with a new brand of potting soil to see if you have the same or different results.
Also, you could try purchasing your plants from different sources. The ones you have now may have come to you from the nursery already infested.
There are a number of pests that afflict Primula. Of the culprits listed on University of California, Davis’s Integrated Pest Management site, weevils might be a possibility, as their larvae (grubs) live in the soil. The recommended treatments include parasitic nematodes and trapping of adult weevils. Here is more on this pest, from the Connecticut Agricultural Experiment Station.
What is the difference between Beesia deltophylla and Beesia calthifolia?
In her book Gardening with Woodland Plants (Timber Press, 2007), Karan Junker says the following about Beesia:
“It is normally represented in cultivation by the species B. calthifolia. Apparently embossed veining enhances the flossy, leathery, heart-shaped leaves. Upright spikes of starry white flowers are produced from midspring into summer. Beesia deltophylla is similar.”
In American Nurseryman, vol 194, no. 12 (2001), p.66, Beesia deltophylla is described as a Dan Hinkley / Heronswood introduction grown from seed collected in Sichuan Province in 1996. “Airy, white, 1-foot racemes that appear in May through July; produces corpulent rosettes of glossy, deep-green, heart-shaped leaves up to 5 inches long.” Under the heading of how this plant differs from other species or cultivars, it simply says “durable, evergreen perennial.” It clumps but does not colonize, has a moderate growth rate and prefers light shade, and a well-drained but moist site.
Beesia deltophylla has fewer teeth and less texture, according to this article by Robbie Blackhall-Miles in The Guardian (May 1, 2014):
“A little later [after George Forrest discovered and named Beesia cordata–what we know now as B. calthifolia], Frank Kingdon Ward discovered a second species of Beesia in Burma which was named Beesia deltophylla. Very similar to B. calthifolia, this plant only has about 15 teeth on each side of its leaf as opposed to B. calthifolia’s 50, and lacks the interesting texture in its leaves. To this day, the two species are confused in cultivation.”
Here is more on B. calthifolia, from Flora of China. This site differentiates between the two species in terms of the veining on the leaves.
Do you have a recommendation for a particularly shade tolerant rhodie? I have dappled shade, but also some areas of fairly deep shade. I’m in the Portland, OR area.
Generally speaking, rhododendrons are tolerant of shade, but need some light if they are to produce flowers. According to Rhododendrons in America by Ted Van Veen (Binford & Mort, 1969), “the larger the leaf, the more shade required … In the Pacific Northwest … most varieties look their best if they have about one-third shade when the sun is warm.”
Dappled shade should be fine for most rhododendrons, but deep shade might mean that you end up with a non-flowering shrub. Look for large-leaved species or hybrids. These are sometimes referred to as elepidotes (generally, this term refers to hybrids with large leaves and flowers that grow in relatively large clusters).
Below are just a few examples of the hundreds of species and hybrids available. (Images and information from Oregon State University are included)
R. catawbiense
R. macrophyllum
Marjatta hybrids
Here is a list of Proven Performers for Oregon, from the American Rhododendron Society:
(These are the recommended large-leaved cultivars from the Portland Chapter:)
- ‘Blue Peter’
- ‘Cynthia’
- ‘Lem’s Cameo’
- ‘Mardi Gras’
- ‘Mrs Furnival’
- ‘Odee Wright’
- ‘Taurus’
- ‘The Hon. Jean Marie de Montague’
- ‘Unique’
