Dec 13, 2015: I know I started out with 12 but, on reconsideration, I really think there's truly only eight.

Here in Oregon we have 2 types of mistletoe, a hemiparasitic (think semi-parasitic) evergreen one and a Evergreen mistletoeEvergreen mistletoeparasitic one, dwarf mistletoe. The evergreen mistletoe is what we use at Christmas time. In the Pacific Northwest, it's typically found growing on Oregon white oaks (Quercus garryana) and is spread by birds eating the white berries and then depositing their dung on other branches. Oddly enough, the name mistletoe is derived from the Anglo-saxon words for "dung stick". Standing under the dung stick just doesn't have the same je ne sais quoi though.

Our evergreen mistletoe (Phoradendron villosum) is called a hemiparasite because it taps into its host trees to obtain water. It manufactures its own food through photosynthesis (that's why its green) but Dwarf mistletoeDwarf mistletoethrough root-like structures called haustorium they penetrate into the branch and tap into the plant tissue to extract water and nutrients. The relationship for the host tree is not a beneficial one. It saps the tree of resources but does not kill it. Our native full parasite, the western dwarf mistletoe derives everything -food, water, nutrients- from the host plant. Dwarf mistletoe is not green (it's a sickly yellow-orange) and causes serious stunting and mortality to the trees it infects, which are Ponderosa pine, Douglas fir and western hemlock, in our area.

But enough of the biology stuff, you're saying, let's get to the symbolism. You guessed it. The Celts, Romans, Greeks, Christians and even the Norse all had symbolic and ceremonial uses for mistletoe. For the Norse Vikings, trees with mistletoe in them acted as ceasefire zones, a pillage free place of peace where truces could be discussed. It wasn't a far stretch then for warring couples to kiss and makeup underneath it and now to today where anyone, warring or not, can get a smack under the Kissing Bough.

Next Christmas party your newfound mastery of mistletoe trivia will make you a big hit. You'll bound to score quick standing under the dung stick. Trust me.



Dec 12, 2015: Ivy, the old Christmas associate of holly, is an evergreen. Most Christmas plants are evergreen. Deciduous plants have never figured big for the holiday season. I guess that's why they call it Christmas greenery and not Christmas twiggery.

The Celts used ivy as winter home decor thousands of years ago. Its winter greenery was a symbolism of resurrection and life to them. The Greeks, on the other hand, associated ivy with fidelity because of its propensity to cling to things. The Romans associated it with Bacchus, the god of wine, and wore ivy wreathes on their head to prevent intoxication. In Christianity, ivy had a more checkered past. At first, it was considered satanic as it grew in the shade and hence could be associated with deception and debauchery, but then somehow that view changed. It was reaccepted into the approved list of Christmas flora because ivy clings to things and hence reminds us of how we should cling to God.

I find all these botanical symbolic interpretations to be interesting but perhaps a bit dated and less relevant to our concerns today. I think it's time to start new plant symbolisms and I'm ready to suggest a few. From looking out my window into my yard, here's a few I can think of. The big leaf maple tree symbolizes to me bowel troubles. Every fall it drops its big leaves which clog my gutters and downspouts. My larch, a deciduous conifer that drops its needles every fall, symbolizes male hair loss. The old red alder tree by the creek, which has got crown dieback and heart rot and has fungus conks growing on it, symbolizes the gradual decay, yet tenacity, of old age. The . . . . you know, this is starting to sound a little too personal. Maybe it's best to stick with the take of the ancients.



Dec. 10, 2015: It is the holiday season, a time of friends, family, reflection and shopping . . . or its avoidance (the shopping, I mean, but maybe some family, too). If you choose avoidance, as I do, it's best to have a good excuse and mine is writing this laborious blog on traditional Christmas plants.

THE HOLLY: Holly's association with Christmas began back in Roman times. Holly was the sacred plant of the Roman god Saturn and during Saturnalis, the wintertime pagan celebration of Saturn, holly sprigs were used to decorate Roman houses and hair. Early Christians adopted the holly custom, to avoid detection and persecution for their Christmas observances taking place at the same time. Something to keep in mind next time you're trying to avoid the law.

Celtic druids also considered the holly a sacred plant symbolizing fertility and long life. Holly boughs attached to the house were believed to protect against lightening and evil spirits. Holly was thought to also determine which member of a household couple would have power in the coming year. If a sprig of holly was brought into the house and the leaves had spines on them, then the male would be dominant in the house. If the leaves were smooth, without spines, then the female would be the dominant member. Many holly species, and there are about 400 of them, exhibit leaf dimorphism, having different leaves on the same individual. English holly, the kind most often used for Christmas wreaths, have both spiny and smooth leaves. So before you go decking your halls with boughs of holly , look at them and carefully consider how this might change the family dynamic of your household. If only I had know this in my first marriage.

Holly, English holly to be precise, has been a commercial crop in Oregon since the nursery industry first started in the mid-nineteenth century. Hollies have the unique characteristic of being dioecious, having male and female individuals. It's the females that produce the bright red berries that festoon our Christmas wreathes. Legend has it that holly growers used to go out into the holly fields and shoot the female trees with bird shot in order to get them to produce more berries. I don't know if the legend is true, but there is actually a biological basis behind that. That, however, gentle reader, I will leave to another future blog on torturing trees for fruit and berry production.

"Here's to holly and ivy hanging up, and to something wet in every cup!" - Old English toast



Dec. 3, 2015: I have always been interested in the junction where history and botany meets. One of the more peculiar junctions involves the horse chestnut tree and how it won World War I and started the nation of Israel (well, it kinda helped, but that's not as dramatic)

The horse chestnut, a native of the Balkans, is used as a street and ornamental tree throughout Europe and North America. It's large brown nut is contained in a green spiny husk and, unlike the sweet chestnut that is edible, the horse chestnut is poisonous.

In Britain, the nut is called a conker and a game, "conkers", is played where the nut is suspended on a string and one swings it into an opposing players nut to see if you can crack it. There is even a World Conkers Championship. In the US, as a child, we used throw the nut, with spiny husk attached, at each other's heads to see if we could get them to stick. I don't recall how we scored those matches but it was much more violent than the English version. I recall having been scored upon several times.

But, I digress, back to WWI and the horse chestnut. In the spring of 1915 Britain was suffering from The Great Shell Shortage. Stores of cordite, the stuff that makes high explosive shells go boom, were dangerously low. It was so bad that artiliery and naval guns were rationed four shells a day. Since 1889, Britain had replaced gunpowder with cordite as the explosive agent in shells. Cordite is a mixture of nitroglycerine, petroleum jelly and gun cotton and the chemical process to produce it required large quantities of acetone. Acetone was produced by the destructive distillation of wood and whole forests were cut and burned to keep the shell factories going.

Britain did not have enough wood to meet its ammunition needs and relied on the forests of North America to supply it. The problem resulted from shipping that wood to Britain through German sub infested waters. It wasn't working. British Minister of Munitions, David Lloyd George, enlisted the aid of a Jewish chemist, Chaim Weizmann. Weizman developed an acetone production process that could use varied forms of cellulose, such as corn or potatoes. Once again there was a problem because corn and potatoes were needed to feed the English populace and troops.

So where do you find an abundant supply of cellulose that's not a foodstuff or wood? Turns out there's a whole lot of horse chestnuts in Britain. The government put out an appeal to the schoolchildren of Britain to collect the nuts. In short order, the patriotic (plus a few shillings per hundred pound bag) kids collected so many horse chesnuts that tons of them were left rotting by the railway. Shell production was back on track and the Brits were back to bombing the bejesus out of the Germans.

Chaim Weizmann, the Jewish chemist that made this possible , became a venerated member of British political circles. Chaim was also an ardent Zionist and argued passionately within those political circles for the formation of an independent Jewish nation. In 1917 his persuasion lead to the Balfour Declaration, which was a promise by the British government to help form a national homeland for the Jew out of Palestine, then in control of by the Ottoman Turks. It was the first in a long series of steps to the birth of Israel and Weizmann later became the first president of the nation.

And that's how the horse chestnut conkerd Germany, won WWI and started Israel (or sorta, kinda). If I had known all that as a kid, it would have seemed less painful having them stuck to my head.


Oct. 18, 2015: Now that the rains have come, our dangers of drought are allayed for the winter, it's not a reprieve for trees though. The effects of environmental disorders, such as too little or too much water, soil contaminants, etc., are not experienced immediately. Much like chronic diseases in people, most environmental disorders take time to eventually kill a tree.

This summer was our second drought in a row and I observed a number of trees in client's yards that were showing signs of drought stress. Stress in trees often times leads to them succumbing to disease and insect attack.

A good example in our area is the bronze birch borer. The beetle attacks European birch. The adults fly to a birch, chew through the outer bark, and deposit their eggs underneath it. The larvae that hatch chew up the inner bark and cambium layers. This "girdles" the branch or trunk, in this case severing the phloem which carries food to the roots. The roots associated with those branches die and then the branches die. The flagging and dying branches in the crown this summer came from larval damage done the summer before. Trees that are stressed by environmental factors are more likely to be attacked by the borer.

So drought will lead to tree stress , will lead to pest attack, which may lead eventually to tree mortality. That process could be a couple of years. So next summer, I'm guessing we'll see a lot more declining trees due to those dadgum opportunistic pests and diseases.

Next year I expect to see more problems with:
European and Himalayan Birch

Douglas Fir: Here pine beetles and twig weevils will be the culprits and well as plain drought stress. Watch out for excessive needle drop from the inside of the tree progressing outward.

Oregon white oak and Oregon ash: Even these native trees that are adapted to our dry summer are showing signs of drought stress this summer (browning of the leaf ends).

Flowering dogwoods: The dogwood is a drought indicator tree because of its shallow root system. I expect to see some leaf scorch (browning of leaf edges) and outright branch dieback.

The list could go on. Our winter weather forecast is not going to help matters as forecasters are calling for a warmer drier winter due to El Nino. ("The Child'?, I really think it should be called El Mocoso, "The Brat" ).

I hate to be a" Debbie Downer" but it's not looking good for next year. What to do? Monitor the trees for health and water, if it's dry. I've never been an advocate for watering established trees, but this summer I will be.

To your and your tree's health.

F & P