Elisabeth C. Miller Library

Gardening Answers Knowledgebase

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Recently Added Questions

Question:

Ladybugs: are they beneficial? Invasive? I know that nurseries sell them for release into the garden. Is that a good idea?

Answer:

The type of ladybug most often for sale is an introduced species. This factsheet from Linda Chalker-Scott of Washington State University provides a thorough explanation of why it is problematic.

Multicolored Asian lady beetles are generalist predators and they can be beneficial in the garden, but they also displace the North American native species of lady beetle. Purchasing them is not recommended and is probably a waste of money because, well, they have wings, and they will fly away. Former University of Washington Botanic Gardens director Sarah Reichard’s book, The Conscientious Gardener, advises that you instead avoid using insecticides so that your landscape will naturally attract beneficial insects, particularly native ones.

Another drawback of releasing ladybug larvae in your garden is that they sometimes find their way indoors, where you don’t want them to be. The multicolored Asian lady beetles (Harmonia axyridis) look for crevices to spend the winter hibernating and they seem particularly fond of light colored south walls. If you don't want to find thousands of these beneficial insects flying around your house on the first sunny day in spring, fill the cracks in your house siding with caulk. For a description, management ideas, and detailed vacuum cleaner bagging instructions, Ohio State University Extension has a fact sheet on these insects. Inside a home, the insect droppings are a human health hazard, and can trigger asthma and other allergic reactions.

Question:

[Tiliagall] cover

On my walk this morning, I saw bizarre lipstick-red protrusions on leaves near the bottom of the tree, where bright green new shoots had sprouted. The tree had kind of sticky heart-shaped leaves, some of them about the size of the palm of my hand. Are these insects? A fungus or disease?

Answer:

Your photos show new growth on a linden tree, possibly large-leaved linden (Tilia platyphyllos). The red things are called nail galls (Eriophyaes tilia) and they are caused by the red nail gall mite.

According to Margaret Redfern's book Plant Galls, this type of gall (in the form of a pouch) is "initiated in the spring by the fundatrices, females that have overwintered in cracks and crevices in the bark or under the scales of dormant buds." The mite will wander over a new leaf's underside and feed on individual cells which then collapse and die. The leaf domes up into a pointed pouch around that area. When the pouch is partly formed, the female mite lays her eggs inside it. The larvae hatch and feed there. Tilia nail galls have a thick nutritive layer, and each gall can contain 100-200 mites by summer. In fall, they disperse and overwinter.

Question:

How did the dog rose get its name?

Answer:

The name dog rose, or Rosa canina, can be traced as far back as ancient Greece. The Greek physician Hippocrates, and later the Roman naturalist Pliny, believed that a cure for the bite of a rabid dog could be made from the roots. There are alternate theories but their histories cannot reach back as far. Some say the name is from 'dag' rather than dog, and that it refers to the dagger-sharp thorns. But this seems implausible, given how many fiercely thorny rose species there are. Some also claim that is it a pejorative name, as in 'a dog of a rose,' an inferior flower. Again, there is no history backing this theory. According to Elsevier’s Dictionary of Plant Lore (edited by D. C. Watt, Academic Press, 2007), the medicinal property of the the rose's roots came from a mother's dream about her soldier son who had been bitten by a mad dog. In the dream, a voice told her to make a decoction of a wild rose’s roots, "which they call Cynorrhodon," and she followed this advice, healing her son of his ailment.

Question:

Do you know how to find out what species or variety of sumac is used in the spice mix called za'atar? I googled it after reading about it in a Lebanese cookbook written by Mary Laird, but the recipes all just say "sumac berries with salt spray left on them!" Are there different versions of the spice mix in Israel and Arab countries?

Answer:

There are many variations of za'atar--Syrian, Lebanese, Israeli, Palestinian, etc. I'm going to go off on a bit of a tangent from your question about sumac, because the identity of the main ingredient of za'atar is a bit complicated.

One primary difference, these days, between Israeli, Palestinian, or Jordanian za'atar, and za'atar made anywhere without plant protection laws is that the picking of Origanum syriacum (the main ingredient of za'atar) is prohibited in Israel, the West Bank, and Jordan because it is an endangered plant, and there's a hefty fine if you're caught harvesting it in the wild. (Sources: Gil Marks, Olive Trees and Honey 2005, and "A political ecology of za'atar" by Brian Boyd in Environment and Society, 2016).

The word za'atar means 'hyssop,' as in the common name for Origanum syriacum, rather than Hyssopus officinalis, which would be too bitter to eat. (Marks says that the plant mentioned in the Hebrew Bible--the Torah--is ezov, which is hyssop, but again, those bible writers weren't necessarily botanists, so they are believed to have meant O. syriacum.) For more discussion of biblical botanical confusion, see Old Dominion University's page on bible plants.

Gil Marks's recipe for za'atar is as follows:
1/4 c. brown sesame seeds
1 c. Syrian oregano (aka white or Lebanese oregano) or alternatively [if you're not a lawbreaker]: 2/3 c. dried thyme and 1/3 c. dried wild or sweet marjoram
2-4 T ground sumac or 1 T lemon zest
1/2 tsp table salt or 1 tsp kosher salt (optional)

My handwritten recipe which is probably from Claudia Roden's Book of Middle Eastern Food, 1968, says:
1 cup dried thyme
1 cup sumac
1/4 cup cooked, dried unsalted chickpeas finely pulverized
3 T. toasted sesame seeds
1 T. marjoram
2 T. salt
Bear in mind that Roden is from an Egyptian Jewish family.

There are probably countless regional variations. The za'atar we used to get in a twist of paper from the bread vendors in Jerusalem's Old City seemed to have very little sumac--it was mostly something like oregano, thyme, sesame seeds, and salt.

And now, back to sumac! Here's a link to an article on sumac in HaAretz by Daniel Rogov (a cookbook author and food writer). He doesn't say which species of sumac is the edible one, but most powdered sumac is from Rhus coriaria.
Excerpt:
"Now before we get to far into this, let us make it clear that edible sumac is not to be confused with Rhus glabra which many people know by its common name 'poison sumac,' which causes severe itching and skin reactions when touched. Those who have lived in North America are probably familiar with this annoying plant which is a cousin of Rhus toxicodendron (poison ivy).
"In preparing edible sumac, the hairy coating is first removed from the berries, which are then ground to powder-like consistency and used by many in the same way that lemon juice and vinegar are used in the West. The spice is probably at its most popular when making mixtures of za'atar..."

Here is additional information about sumac from Gernot Katzer's Spice Pages.

For another discussion of za'atar and its ingredients, see this site from a Society for Creative Anachronism member--it gives you an idea of the diverging opinions about the constituent ingredients.

Question:

My pet cockatiel died, and I want to know how long it will take to compost the bird in the soil before I can dig up the skeleton and save it.

Answer:

I am sorry for the loss of your cockatiel. I think that you can either put the body in the compost or find a way to salvage the skeleton, but not both. Bird bones have hollow cavities, and would likely break down quickly in the soil. Some permaculture discussion groups online suggest not burying birds, but instead storing them in the freezer until there are active ant nests, and then leaving them exposed for the ants to clean. I was not sure if this would work, so I consulted Dennis Paulson, Director Emeritus of the Slater Museum of Natural History at University of Puget Sound in Tacoma.

He says that "putting something as small as a cockatiel in the ground isn't the best idea, as their smaller bones would probably suffer. Putting it near an ant nest might not be much better, as the ants could carry off those small smaller bones. To make a good skeleton, you need to skin the bird and remove a lot of the bigger muscles (in particular, the flight muscles on the breast) as well as the intestines and other organs from the body cavity." The Slater Museum of Natural History can skeletonize small birds by using their colony of dermestid beetles that eat all the soft tissues, which is the best way to skeletonize something of that size. The museum accepts donations of specimens, but they may also be willing to assist someone who wants to commemorate their pet bird in this way.

In general, dead animals that are not pets and weigh over fifteen pounds must be collected by Seattle Animal Control, but smaller animals that show no signs of disease may be double-bagged and put in the garbage. King County has similar guidelines. Dead wild birds (particularly crows and jays) that may have been affected by West Nile virus should be reported to the Public Health department at 206-205-4394.