Make way for new a new cross light in Atherton

About a month ago I sprained my ankle. It was inconvenient, but I was still able to work from this bucket truck. It’s a wheel chair for arborists. I wouldn’t recommend this for fine pruning, but for street clearances I was able to get the job done in record time. The electric company provided the truck. It was fun. But I had spiders in my bucket, eek!

Maytenus boaria, Mayten Tree

The Mayten Tree is a beautiful tree from Chile. It has a gorgeous pendulous branching that looks like a waterfall. BEWARE!!! Although this tree looks spectacular it has the most aggressive suckering roots that I have ever come across in San Francisco. If you plant it in your garden you will have suckers popping up all over the place, possibly in your basement. Also, if you prune this tree too aggressively it will sprout back even more aggressively. So prune lightly; make fewer, larger cuts. Be prepared to have to prune often to keep the desired shape.

Pictured below is a street tree that I pruned in the Castro Dist. As you can see it looks a bit unkempt. I cleaned it up and also planted some succulents in the tree well.


Tree of the Week, Magnolia grandiflora

*Botanical Name: Magnolia grandiflora (grandi means big and
flora means flower, just in case it wasn’t obvious enough).

**Family: Magnoliaceae

***Common name: Southern magnolia (most common in SF), bull- bay, evergreen magnolia.

****Native environment: Virginia to central Florida, Arkansas to Eastern Texas (left).

*****Height: up to 90 feet. Wiki says the biggest ones recorded are in Louisiana; one tree has a trunk18 feet in circumference at breast height; another tree is 114 feet tall. Wow!!

******Likes rich, moist, well drained soil. They do NOT do well if the soil constantly wet. They can tolerate shade when they are younger, but need full sun later on in life.

*******Many cultivars; some with gigantic flowers (up to a foot across), some slow growing dwarf trees, various leaf sizes, colors, and shapes. My friend Waiyde says he has one that has huge, dark purple flowers.

*******Magnolia grandiflora is an evergreen, but they still drop leaves and make a mess. The last time I pruned a magnolia street tree this little old man kept telling me to cut it down completely. He groaned and groaned about it so much we nick-named him “Mona”. He said he was forever having to sweep the sidewalk. Poor Mona; not a very happy man.

Southern magnolias are very common in San Francisco as street trees. They have large, waxy, dark green leaves that are sometimes yellow/orange and fuzzy underneath. The waxiness make them very tolerant of pollution in cities. The big, usually white blooms are quite fragrant. Yum.
It is also the state flower of Mississippi and Louisiana and was an emblem of the Confederate army in the Civil War.
It is also Mississippi’s state tree.

Here are a couple of small magnolias we pruned over on Vicksburg in Noe Valley. I did the pruning, Kent did the ground work. Kent is great at securing the ground, making sure that I am aware of pedestrians walking below. We don’t want anyone getting hurt.

before: after:

Little Metrosideros in the Sunset

Here is what a tree looks like a few years after it’s been badly topped.

It looks like a bit like a shrub on a trunk (right).

Well, we trimmed this poor little tree the best we could. This will be a process of restoration that make take several years (above).
We also planted the tree well with succulents and filled it in with decomposed granite. The bank manager, Rosemarie, was really happy with the outcome. I love planting tree wells.

Black Acacia

The goal for pruning this tree was crown reduction.

Judy had wanted to plant an Acacia baileyana (Bailey acacia), but she ended up with an Acacia melanoxylon (black acacia). Oops. These are two very different trees. Judy had wanted a small tree…

The baily acacia is fast growing and relatively short lived (20-30 years). They have feathery leaves and grow only 20-30 feet.

Leaves and flowers of the baily acacia (below). There is also a variety called purpurea, with purple leaves.

The flowers of the trees in the genus acacia are usually little yellow puff balls (left). Many people in SF complain about their allergies to the pollen. They create a big mess as well…

Acacia bailiana is a very pretty tree for the first 10 years or so. Afterwards they become a bit rough looking. The branches die back strangely so that there are lots of right angles, making them look like a bit like a fuzzy tumbleweed.

The black acacia leaf is lanceolate, meaning long and narrow, but wider in the middle (below).

They also grow very fast and very tall. This is not the tree to plant if you have electric wires overhead, or if you are Judy and you simply want a small tree. The bigger ones here in San Francisco are around 50 feet. In the wild they can get to be as big as 150 feet tall.

I love pruning these trees because they can be made to look spectacular through natural layering. They can look like big, puffy, green clouds.

Judy wanted us to reduce the size of her tree since she didn’t want a large tree in front of her house. We reduced it as much as possible without making topping cuts. She would have liked to have been brought down further, but that would have been bad or the tree.

In order to keep the costs down we kept the design element to a minimum. We worked strictly on crown reduction, not layering.

Here is an after shot of Judy’s tree. As you can see, we successfully reduced the crown while also giving the tree a nice shape.

Kent did the ground work and I did the pruning. Kent’s job is also to occasionally give me an “eyeball.” It’s difficult to see the overall shape of the tree when I am inside the canopy. Kent can tell me if he sees anything sticking out that disrupts the line. He can also assure me that I am finished. Kent studied art in school and he has a good eye for detail.

I’ve been studying the acacia tree as I’m here blogging away. It’s a very complicated tree.

Family: Leguminosae. That is the pea, legume, or the bean family. The third largest family of flowering plants behind Orchidaceae and Asteraceae. 730 genera, 19,400 species.

The word acacia is derived from the word akakia, which is the name given by a Greek botanist. The name is derived from the Greek word akis means thorn.

The following is ripped off from Wikipedia:

“Acacias are also known as thorntrees, whistling thorns or wattles, including the yellow-fever acacia and umbrella acacias. Until 2005, there were thought to be roughly 1300 species of acacia worldwide, about 960 of them native to Austraila, with the remainder spread around the tropical to warm-temperate regions of both hemispheres, including Europe, Africa, southern Asia, and the Americas. However, the genus was then divided into five, with the name Acacia retained for the Australian species, and most of the species outside Australia divided into Vachellia an Senegalia.”

That’s enough for now. Soon it will be Tree of the Week and I’ll ply you with more.

Too big for its pot

I was called out to trim a large, 30 year old Pittosporum undulatum. From below I could see that there was some disease.

When I climbed into the canopy I found out that the disease was much worse than it seemed.
There was die back along the main branches. There were also mushrooms. Mushrooms in trees is a sign of rot on the inside of the tree.
The reason why is that this tree got too big for the pot in which it was planted. 30 years ago it was just a little tree. Today, it is massive.
We didn’t want to remove the tree right away. A most trees do, it has a lot of sentimental value (as well as aesthetic). Laura planted it herself 30 years ago when it was just a tiny sapling; when it was the only tree on the block. She had no idea that it would become so large. The tree will have to come down some day. We’ll keep an eye on it for now. Fortunately Laura also planted a sidewalk tree so that the space won’t be completely bare when the Pitto is gone.
These Pittosporums are very stubborn trees. They can take a lot of abuse, but we don’t want to risk a branch falling on a pedestrian on thesidewalk. So we removed some major limbs, reduced the weight of the diseased branches and made a commitment to monitor the disease over the next few years.
We also pruned a New Zealand Christmas Tree that was in the sidewalk. I did the pruning and Kent took care of the ground work. Here are some before and after photos:

Here I am contemplating the big job before me.

The client wanted this Dodonea in Pacific Heights to be hedged by hand, not with sheers. This would give it a softer edge. She also wanted her hedge to have steps that would coincide with the steps in the garden. Check out the result.
Kent, my trusty groundsman, proved himself to be the best groundsman ever today. One of the biggest challenges on this site was to navigate the extensive garden. We didn’t want to damage any of the beautiful flowers. Kent made sure that nothing in the garden was damaged and that we left the area looking just as pretty as when we had found it. With all those little snips there was quite a lot of cleanup. Somehow he was able to have just about everything back in order by the time I was finished pruning.

This garden was not street level. There were 30 stairs between the garden and the truck where we had haul all debris. The next day Kent was quite sore from having to walk up and down three flights of stairs all day. What a trooper!

Dead Plumb

It was an easy removal. All we had to do was push it over. You can see the girdled, circling roots that eventually caused the tree to die. You can also see the GIANT adventitious root that had grown out of the trunk. This tree died because it wasn’t planted properly. It had been planted too low. Also the circling roots in the root ball had been left uncut.

Here is a lovely example of crown reduction and natural flow pruning. I worked on this Pittosporum undulatum in the Richmond District on 19th Ave and Balboa.

It really looks almost like I never pruned it at all.
From the inside of the canopy it made quite a difference.

Tree planting tips

Yesterday I was called in to look at some sickly plants.

The first tree, really a shrub, had failed at the base of the trunk. It looked like it had rotted out. Upon closer inspection I found an old irrigation head that had been engulfed by the trunk. I’ve seen this happen before. Landscape companies sometimes install irrigation heads too close to newly planted trees and shrubs. If they go unchecked then years later they can become engulfed. If they over water, the constant moist soil can cause root rot, sometimes even trunk rot. Eventually parts or all of the tree or shrub will die.

The second tree, a Thuja occidentalis, stood about 8 feet tall with a DBH (diameter at breast height) of 3-4 inches. The leaves had a grayish hue and looked dry.

The problems stemmed back from the time of planting.

The tree was still strapped to the original nursery stake. I gently rocked the trunk back and forth. I could see the outline of the original root ball moving in the ground. The outline was the size of a nursery pot. Not a good sign for a tree that has been in the ground for two years.

I probably could have picked it up out of the ground and put it right back into the pot it came in.

Here are some important planting tips:

1. When you plant a tree be VERY aggressive with breaking up the root ball. Don’t be shy. People often think that the roots are like the intestines of the tree. They aren’t. They are more like the underground branches and can be pruned just the same.

Confined a tiny pot in the nursery, young tree roots grow in circles and become woody. Unless they are pruned they will stay that way and possibly never grow normally.

So break up those root balls. Making clean cuts, cut the woody circling roots and spread out the succulent roots so that they flay outward. This encouraged them to grow normally, like in the direction of spokes on a bicycle wheel.

2. Make sure the root flair is above the soil level. Always plant high. Too high is better than too low, especially in soil with a high clay content.

Often trees in nursery pots have buried root flairs when you get them. Before you plant, make sure you locate the root flair. The root flair is the area where the trunk flairs out to the roots. When I plant trees from out of big nursery pots sometimes I have to remove as much as 6 to 8 inches of soil off the top. So don’t be surprised at how deep you may have to go. Just be gentle not to damage the trunk.

The root flair should always be above ground. It shouldn’t be buried by mulch either. So plant high, plant high, plant high. This goes for just about all plants. As far as I know, the only plant you should plant low are tomatoes.

3. When you plant a tree always remove the original stake that runs along the trunk. Replace it with two or three stakes placed just outside the root ball. Tie the tree up so that it moves slightly in the wind. This promotes strong, healthy roots.

4. The first thing you should do after planting is water. It’s a good idea to build a berm around the tree (or shrub) so that the water doesn’t just leech off into another part of the garden. I like to water by putting a garbage bag in a 15 gallon nursery pot, filling it with water and then poking a small hole in the bottom. This allows for a slow drip to deeply penetrate the roots without leeching. You can use a hose, running on low, but it’s super easy to forget to turn it off. Do this three times a week, rain or shine.