If you are a new homeowner, or simply home shopping, you will want to determine if the trees around the property have been Pollard pruned, and factor the cost of yearly Arborist visits into your budget, or the asking price on a house.  A pollard tree requires large-scale yearly pruning to maintain the overall health of the tree, or the tree will suffer from structural issues, and pose a threat to nearby cars, and property, with regularly falling limbs and debris.

How To Tell If A Tree Has Been Pollard Pruned:

Throughout the fall and winter, a pollard pruned tree will be obvious, with the majority of it’s growth cut away, and no foliage visable.  Through the growing season, these trees may be more readily identified by abnormally thick growth in the crown of the tree, and a disproportionately thick truck of the tree when compared to the height of the tree.  In the height of summer, a pollard tree’s foliage often resembles a mushroom shape, with an almost perfectly shaped dome of leaves rising over the trunk of the tree.  One of the trademarks of the rapid and thick growth following a pollard pruning is that the foliage in the crown of the tree is so thick that you cannot see daylight through the branches. Pollarding cuts off the mature and natural branching of the tree, and capitalizes on the rapid growth of what are called water sprouts. Out of each branch cut will grow wads of small water sprouts, that create a very full illustion of foliage, but a very weak structure. When looking into a fully leafed-out tree to check for pollarding, let your eye follow the main branches up the tree from underneath, and notice if the branches abruptly dead-end into clumps of long finger-like shoots that grow straight up toward the sky.  If you find this pattern repeated through the tree, then you have a pollarded tree.

To the left are two pictures.  The top picture is of a pollarded tree, and it’s mushroom cap growth, and bottom picture is of a tree pruned for structural soundness, but allowed to grow naturally. As illustrated by these two pictures, average foliage growth on a tree that has not been pollarded allows sunlight through, and has been allowed to develop mature branches, that open the tree up, with yearly foliage growth more consistantly toward the perimeter of the crown. Pollarding allows a tree to keep water sprouts, and trains a tree to repeatedly develop them, a practice discouraged in common pruning methods, where branches are carefully selected to bear the load of future years of growth.

If you are house shopping, pollarded trees in the yard, or along a street, that you may become responsible for, are one thing to add to your list of items to ask the prior homeowner about.  Yearly Arborist visits to care for your trees can add up, and will be an item you may want to use in negotiating your settlement.  Unfortunatley, due to the large-scale nature of this pruning method, it is not a practical project for the weekend DIYer, and will require the hauling away of a years worth of tree growth. For new homeowners with existing pollarded trees, contact a knowledgeable arborist in your area to work on a plan to maintain a healthy pollarded tree.  A yearly, or bi-yearly full pruning plan will be needed for the life of the tree.

I was on my way over to my sister’s house, when I passed Arborists in her neighborhood gearing up to prune one of her neighbor’s street trees.  Having seen the final result of the requested “pollard pruning” in years past I came by later to photograph the fresh cuts. This type of pruning is my absolute least favorite, and can give new meaning to the term ’stark,’ leaving the tree with nothing but the bare essentials for the fall and winter months.

“Pollarding” is the once-yearly removal of all the previous years growth all at once, and when done properly requires a skilled and artistic eye, to correctly select the branches that will be kept in the final design. Arguably, this method is designed  to lengthen the life of a tree, and keep the tree size relevant to the space within which it is planted.  For hundreds of years, this type of pruning has been utilized across the great cities of the world as a method of containing street trees, and encouraging uniformity of appearance.  Historically speaking, this method was developed in the days of wood stoves, and earlier still, of hearth fires, when trees were pollarded as a method of guaranteeing a regular wood pile supply for the winter. The trimmings from the tree, including the leaves and young shoots were often kept as winter food sources for livestock. European countries especially hold many trees that were used for these “working” methods, until the last 50-75 years, whereas now much of the pollarding is continued for visual reasons.

The downside to pollarding is that once a tree is pruned with the pollarding method, the tree must always be pruned in this same way, as the top growth out of the cuts are untrustworthy, and weak, and can cause damage to the tree, or nearby property.  Pollards are susceptible to wind and storm damage, when fully leafed out, and when left unpruned for more than one or (at maximum) two years, can actually strangle themselves with the overabundance of shoot growth and water spout growth that becomes tangled in the crown of the tree.

Over time, the appearance of the tree after pruning will alter, and large “knuckles” will form at the top of the branches, as the tree repeatedly heals from repedetive cuts in the same area, and seals and protects itself from the weather. The final result after years of pollarding will produce a rather ominous looking tree trunk shape, a fact not lost on the author of the  “Harry Potter” stories, who designed a rather aggressive character named “The Whomping Willow,” on the appearance of common Willow tree Pollards in England.

My Thoughts: I personally would never apply this technique to my own trees. To the untrained (or concerned) eye, this method looks more like scalping a tree, than encouraging growth, and in the United States, where this method is used infrequently, the appearance of the trees especially through the fall and winter months may repell homebuyers if your house is on the market.  Unfortunately where curb-appeal is king, this method often will not provide a return on the yearly investment you make with local arborists, in the care and upkeep of this high-maintenance method, and will be an item that either you, or the homeowners that follow you, will need to build into the yearly budget throughout the life of the tree.

Your Thoughts: What are your thoughts on pollarding?  Do you own a pollarded tree?  Would you ever used this method in your own yard?

White Ash trees have a reputation for having very strong and flexible wood, but when I drove past this tree on my job site, I knew I had a serious problem! Generally a tree bent and straining in this manner is suffering from severe drought conditions, and is in danger of losing branches under the strain of holding it’s own weight up! This year has been particularly rainy on the east coast, so this type of appearance in a tree was a little confusing at first, especially in a tree that had shown no signs of insect damage.

White Ash trees are an American native tree, rarely prone to disease, although they are vulnerable to the Emerald Ash Borer and Verticillium Wilt. I quickly checked the tree and saw no Borer holes entering the tree’s trunk - although insects and birds seemed to be showing a peculiar interest in this and two other surrounding trees. The branches on all three White Ash trees showed healthy summer leaf growth and color, even though they were bowed way down over the nearby sidewalk. To my eye, these trees did not appear diseased, so diagnosing the cause of their stress related appearance was out of my league.

I contacted a knowledgeable arborist, who found a simple answer to my puzzle. Heaps of green flowers and red clusters of what looked like tiny dried Chili Peppers, were clinging to the branches all over the tree, in what was an off-season burst of blooms. Bees, wasps, and birds were constantly darting in and out of the tree, in what turned out to be a feeding frenzy, rather than a sign of insect infestation, as several neighbors feared. Apparently, several types of birds feed on the seeds of Ash trees, and the pollinators, and carnivorous bugs were feeding on the massive amounts of nectar, or tiny pests that had been drawn to the tree. The arborist was perplexed to discover that the tree had both leafed-out for the summer, and exploded in an unprecedented amount of blooms, when the two functions on the tree are not supposed to occur at the same time. Blooms on a White Ash tree are supposed to precede leaf growth, and be small, and barely noticeable! This tree was simply weighed down under the weight of it’s own abnormal fertility, and the prescription for the tree was to simply let nature take it’s course. The White Ash blooms will dry up, the rest of the “chili pepper” seed pods will drop off, and the tree will regain it’s upright stature in the next few weeks.

This is one of those times when the simplest answer to a problem can be staring you right in the face, and you don’t even see it, because you are going “by the book.” I am not sure if the unusual amount of rain we received, or the cooler than average temperatures contributed to the trees apparent fertility confusion, but either one could have thrown the tree off it’s regularly scheduled program.

I am doubly glad though, as I am writing this, that I did contact someone with the experience to recognize the cause to my problem. This tree apparently did not read the textbooks on how it was supposed to behave, and had I applied any treatments to the tree to keep the birds, and wasps off of the tree, I would have robbed the local ecosystem of what was apparently a valuable food source.

Your thoughts: Have you ever run into something in your yard or garden that just didn’t quite seem to make sense and later realized it was something fairly unique going on?