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Can you tell me if Acacia trees grow in Seattle? Could I obtain a small cut branch from one? I am a funeral director, and the last wishes of the deceased we will be burying were to have a sprig of acacia placed inside the casket. This man was very active in the Freemasons, and evidently the acacia is an important symbol for them.


Most Acacia species are marginally hardy in our area. According to local tree expert Arthur Lee Jacobson, most gardeners who plant Acacia end up with a large pile of exotic firewood once the trees have died off during a serious winter. Therefore, your most likely source for a cut sprig would be to ask local florists, who obtain this plant regularly for use in flower arrangements. You can also contact the source the florists use, Seattle Wholesale Growers Market (where they will order it from California).

In Freemasonry, acacia symbolizes the soul's immortality, perhaps because of the evergreen foliage. The book of Exodus in the Hebrew bible seems to have been the inspiration for choosing this tree, called shitta [singular] or shittim [plural]. According to the text, the wood was the raw material for the Tabernacle and its contents, the Ark of the Covenant, the Altar and the Table and the Pillars of the Curtain. Biblical botany scholar Lytton Musselman speculates in his book Figs, Dates, Laurel, and Myrrh (Timber Press, 2007) that the species might have been Acacia albida, now renamed Faidherbia albida. However, the masonic texts have another view. According to Mackey’s Encyclopedia of Freemasonry, "It is the acacia vera of Tournefort [refers to 17th century French botanist Joseph Pitton de Tournefort], and the mimosa nilotica of Linnæus. It grew abundantly in the vicinity of Jerusalem, where it is still to be found, and is familiar to us all, in its modern uses at least, as the tree from which the gum arabic of commerce is obtained."


Last fall, I raked up my fallen cherry tree leaves, and put them in my vegetable garden bed to use as leaf mulch. I don't know what our cherry tree species is, except that it appears to be ornamental. Then I covered the leaves with burlap coffee bags to winterize the garden bed.

I've recently heard that cherry tree foliage and twigs release cyanide when they wilt and decompose. Does this mean that there is cyanide in my garden soil? And if so, will the cyanide be transferred to any vegetables that grow in it? Safe, or unsafe?


A general rule of thumb with fruit trees (in case your cherry is an edible cherry variety) is to gather up fallen leaves under fruiting trees and remove them for good garden hygiene (preventing the spread of disease and any unwanted insects). Provided your cherry is healthy, I don't think the leaves would pose a serious problem if used as leaf mulch on top of the vegetable garden beds.

The leathery evergreen leaves of English laurel (Prunus laurocerasus, same family as deciduous cherries and plums) are not a good choice for the compost pile because they take a very long time to decompose (which is not the case with deciduous cherry), and they contain cyanide compounds. However, so do apples, plums, almonds, peaches, apricots--all have some cyanide in them.

This link briefly mentions the question of cherry leaves and cyanide in terms of toxicity to animals. Fresh new leaves have a higher concentration of hydrogen cyanide; toxic potential is gone when the leaves turn brown. True enough, this is about eating the leaves, not letting them sit on the soil, but I imagine the concentration would be very low, and there are all sorts of things in our soil that in small doses are not likely to cause harm, and may or may not even be taken up into the roots of anything you plant there.

I asked Washington State University Extension Horticulture professor Linda Chalker-Scott what she thought about the safety of using those leaves and twigs on your vegetable bed, and she said, "Cyanide does not persist in soils. It is HCN [Hydrogen cyanide], which is quickly broken down by microbes in search of nitrogen. It is really nothing to worry about.


While visiting the Kona side of Hawai'i, I noticed a low shrubby plant with stunning white flowers that had many long stamens. Can you tell me what its name is (both the scientific name and common name)? Is it something that could grow in a Pacific Northwest climate?


The plant in your picture is Capparis sandwichiana, or Hawaiian caper. Your description pinpoints one of the most striking features of this shrub, its numerous, showy stamens. In Hawai'i it is called maiapilo or pua pilo. According to A Tropical Garden Flora by George Staples and Derral Herbst (Bishop Museum, 2005), it prefers the hot sun and salt spray of coastal coral flats, rocky cliffs, or exposed lava flows further inland. It is used in rock gardens, and as a ground cover in seaside gardens, and on slopes and banks. The plant has traditional medicinal uses for treating skin, bone, and joint injuries.The name pua pilo, 'stinking flower,' is a bit of a misnomer. The flowers, which open at sunset and last only one night, are sweetly fragrant. It is the cucumber-shaped ripe fruit and the leaves (when handled) that are malodorous. It does not produce the capers that are known for their culinary uses. Those capers come from the buds of Capparis spinosa.

According to the United States Botanic Garden, Capparis sandwichiana is vulnerable in its native range (Endangered Species status) due to development of the Hawaiian coast and lowlands.

Neither species of Capparis would thrive in the Pacific Northwest. Capparis sandwichiana is suitable for Zone 11. Capparis spinosa, a Mediterranean species, is Zone 8-10, but at zone 8b, we are a marginal location for this plant. Pacific Northwesterners who yearn to make their own edible capers can try pickling Nasturtium seeds, as described in this Oregonian article (August 2, 2009, Vern Nelson). I suspect, however, that it is the flowers that captured your imagination!


I found a reference to a type of edible gall that grows on sage plants in Crete, and is sold as a sweet in markets there. Can you tell me what species of sage that might be, and is it something we can grow in the Pacific Northwest? Will it develop tasty galls here?


It seems very likely that the species of sage is Salvia pomifera. That species name ('fruit-like') refers to the apple- or fruit-shaped galls. The webpage of Flora of Israel has a feature article by Professor Avinoam Danin on this type of Salvia that does indeed grow in Crete. He mentions another Cretan species that produces fruit-like gall structures, Salvia fruticosa.

Flowers of Crete (John Fielding and Nicholas Turland, Kew, 2005) describes these two common shrubby sages found in Crete. "They share similar habitats, pine woodland, olive groves, scrub, garrigue, and rocky places," though S. fruticosa is mainly found in the lowlands, while S. pomifera is more montane. Salvia fruticosa (faskomilo in Greek) is used in herbal tea, but "both species produce globose stem galls, which are eaten raw (including the insect larvae inside) by Cretan children." (The authors do not say why children--rather than adults?--prefer this treat!)

According to Greek horticulturist and Salvia expert Eleftherios Dariotis, "Salvia pomifera is the one that produces most galls and people like to eat them. Their taste is like a sagey apple and they are crunchy in texture. S.fruticosa produces galls as well, but not as often."

In the Middle East, there is another species of sage that produces edible galls. Salvia dominica goes by the common name Bedouin peach, or khokh, because the galls it develops are fuzzy like the fruit.

The galls aroused curiosity among plant explorers in centuries past. 16th century French botanist Pierre Belon described them as "covered with hair and sweet and pleasant to the taste. They were collected at the beginning of May and sold by the people of Candie [Candia?] to neighboring villagers." [Source: The American Naturalist, Volume 52 February-March 1918]

During his travels in Crete, the 17th/18th century French botanist Joseph Pitton de Tournefort came across a sage he called 'Salvia cretica frutescens pomifera,' a shrubby Cretan sage that bore apple-like fruit. An article in Saturday Magazine (vol. 16, 1840) mentions his observation of large galls "caused by the punctures of insects; these galls are firm, fleshy, semi-transparent tumours, swelling out from the branches of the plant, and supposed to be produced in the same manner as oak apples, by the puncture of an insect of the Cynips genus. They form an article of ordinary sale in the markets, and are called sage-apples. When preserved with sugar, these apples are regarded as a great delicacy."

Salvia pomifera will grow in USDA hardiness zones 7-10, and both Salvia fruticosa and Salvia dominica will grow in USDA hardiness zones 8-11. To me, that sounds like potentially marginal hardiness given our tendency for wet (Salvia-rotting!) winters.

I have a feeling that you would not have much luck in attracting the right species of Cynipid gall wasp to Pacific Northwest-grown Salvias. The Aulax species of gall wasp is what causes the galls found on sage species growing in the Mediterranean region. According to the Field Guide to Plant Galls of California and Other Western States by Ron Russo (University of California Press, 2006), the gall wasps which may affect Salvia species in California and other western states are Rhopalomyia species. The galls they form are tubular in shape, and not fruit-like in appearance. There is no documentation on their taste.


I am setting up a native plant garden in Seattle this fall. Since the plants I'm choosing are adapted to our dry summers, is it OK for my landscape to go without supplemental water next summer?


Expect that your new garden will still need some supplemental water next July and August. People often ask why it is necessary to water plants that can grow with just rainfall in the wild. Depending on the situation, though, it can be essential for several reasons. Our city gardens often have hot areas of paving nearby, and soil that's compacted, sandy, or poor compared to forest or meadow soils. Wild plants spring up from seed or spread underground to where they can find water and other necessary conditions for their species, while the roots of transplants must suddenly support a whole plant in a new environment that is likely quite different than the native plant nursery where they were grown, and may also differ from the conditions for which they are ideally adapted. Climate change is a factor, too.

A great book that can help you with planning and maintaining landscapes with our native plants is April Pettinger and Brenda Constanzo's Native Plants in the Coastal Garden. The authors emphasize the importance of siting your native plants well, in communities of plants that are suitable for the conditions you have. Their list of plants for dry places may be helpful to you if you are still choosing plants.