False Spring Has Arrived

Our cool summer followed by a brief but intense period of heat has tricked some plants into thinking it's spring again. This 'False Spring' is pretty common here in Southern California, happening at least once every 5-10 years here or more. The fun thing about these not-so-common weather patterns is that they seem to affect different plants each time. This year our 'False Spring' has caused our 'Tower of Jewels' (Echium wildpretii) to bloom out of the seemingly dead clumps of last years plants. Since 'Tower of Jewels' is a biennial, I guess these would be 'triennials'.

'Tower of Jewels' (Echium wildpretii) blooming in fall from an old, mostly dead bloom cluster from last season.



Magnolia X 'Galaxy' blooming out of season due to the 'False Spring'.

 Fuzzy critters attacking oak trees? No, just a type of gall wasp that causes a furry but benign gall to appear on the leaves.



Live-oak wooly leaf galls.

 

 Hops (pictured above) are the female flowers of the hop plant (Humulus lupulus)extensively used in the beer industry as a flavoring and stabilizing agent. These are growing in our herb garden.

Plant Identification Class Starts Today

My plant identification class starts today at 2pm. We'll be doing a lot more field work in this session so I'll be posting Google photo albums with pictures of the plants we'll be working with as well as their locations. I've also started a new blog that will have links to these photos as well as links to identification sights and other useful information.

Devil's Coach Horse Beetle

Ocypus olens

This fascinating looking insect was found walking across the road in front of the Peacock Cafe. It is a type of beetle known as a 'Rove' beetle. This particular species (Ocypus olens ), is a European native that was introduced to Los Angeles sometime in the early part of the 20th century. They feed on snails, slugs, earthworms and other invertebrates  If you see one here at the Arboretum please enjoy it from affar, although they don't sting they are rumored to have the ability to use their powerful front pincers to deliver a rather painful bite.

Defensive posture of Ocypus olens, see those pincers! They gonna bite ya. 

Ocypus olens in a more relaxed state. 

"Pumpkin on a Stick" Is Not





Now that it's Fall you'll probably see this thing in flower shops -it's marketed as 'Pumpkin on a Stick" It's not a pumpkin at all nor is it closely related, it's Solanum aethiopicum, also known as the Ethiopian nightshade. Is it invasive? Is it poisonous? Where did it come from?

It is not on the USDA's invasive plant list, it is not listed as poisonous and is widely eaten in Africa where it is native, but always use caution with anything in the genus Solanum (for some real unnecessary alarm read here about a poisoning involving a different Solanum species). That being said it can be grown from seed and can get 8 feet tall. It takes 70+ days to fruit so you should plant it in the first week of August to get fruit by Halloween.

Solanum aethiopicum

A Brush Cherry Apart

 This has always been intriguing to me -a variegated Syzygium australe. It appeared as a 'sport' on an otherwise green S. australe here and has remained stable (not reverting back to its green appearance) ever since.

Syzygium australe

Plant Information Class Tour of Nuccio's Nursery

Seven hardy souls braved the 100 degree plus heat to show up at Nuccio's camellia nursery for a tour by owner Tom Nuccio. They weren't disappointed as Tom not only discussed the varieties of camellia they had to offer but  gave us tips on how to propagate them using seeds, cuttings and grafts.

Tom Nuccio shows off some of his species camellias from China and Vietnam.

These two and tree gallon pots are full of newly germinated camellia seedlings. Tom told us the trick was to plant the seeds as soon as the seed capsule ripens.

According to Tom camellias will root almost anywhere on the stem, so you need only one leaf node per cutting.

Tom shows us a newly rooted camellia cutting. 

Camellia cuttings root in Tom's mist house. 

Tom explaining that Dragon fruit cactus like climbing up smooth surfaces, like the bark of the citrus tree that this one particularly robust plant is growing on. 

Greenhouse full of newly grafted camellia plants. 

Tom's grafting secret? Mason jars are kept on the newly grafted plants until callous and new growth is observed. 

Tom points out new callous growth on a camellia cutting as well as a new leaf-bud. 

New growth on a camellia graft -Tom revealed that tipping the mason jar over just a bit the for two to three days before it is removed allows the cutting to acclimate before it is exposed to the drying southern California air. 

Tom also gave us a demonstration on how to do camellia cuttings. 

• Nuccio's Website
• Video of Tom Nuccio Demonstrating his Grafting Technique. 

Tiger Bee Fly

A guest brought in a dead branch from a mulberry tree that had large tunnels bored into it. I recognized these tunnels as Carpenter bee galleries. Carpenter bees usually attack already dead wood so I wasn't too concerned until I saw this monster flying out of the gallery (luckily the whole thing was in a plastic bag). 

Tiger Bee Fly, about an inch and a half wide -he's a big boy.  

This was a Tiger bee fly. A very pretty and non-disgusting member of the fly family. And it east Carpenter bee larvae, in fact their was a Carpenter bee larvae mummy, probably the victim of the Tiger bee's own bee eating larvae, located just inside one of the tunnels (see below) 

Carpenter bee larvae mummy, a probable victim of the Tiger bee fly.

Details on September Plant Information Class

Plant Information Class on September 4^th at 1:30. Meet at Nuccio’s Nurseries.

This month’s plant information class is a tour of Nuccio’s Nurseries located at 3555 Chainy Trail in Altadena. Nuccio’s specializes in all kinds of Camellias and Azaleas and if you think these plants are heavy water users then you will be pleasantly surprised as you find out otherwise from Nuccio’s staff as they will tour us around the facility and tell us things about these plants that you might not already know.

Plant Identification Class Coming in October

Don’t forget to register for Plant ID class in October –we’ll be covering a lot of new families including several conifer families like Pines and Araucarias.

Seeking Pitcher Plants in the Philippines

We watched a video during today's monthly plant information class that was just fascinating. Here it is: 

An Evil Looking Seed from Yonkers

Trapa natans L. the Eurasian water chestnut

I love a good mystery and sometimes this job delivers. A visitor who had been to New York a week before superstorm 'Sandy' found this on the shore of the Hudson river near Yonkers. This is one of the strangest seedpods I've seen in a while (I was assuming it was the seed or seedpod of something that had floated to its final resting place there on the shores of the Hudson). Now I've had strange floaty seeds brought into my office before but this one took the cake. It had a distinctly evil looking appearance (at least by Disney villain standards where most villains have a pointy chin and ears). After typing in such esoteric terms as 'litoral trigonal capsule' and many other permutations of the same into Google with no luck at all I typed 'seeds washed up on a shore' and there it was, the third picture in the image results from Google.  Sometimes it pays to keep it simple, even in botany. Turns out it was Trapa natans, also known as the Eurasian water chestnut, a plant that is an invasive water weed that ranges from Virginia to Vermont.

Bugs and Fungus Come Into My Office

Mushrooms

These were brought in by a woman who was worried about mushrooms poisoning her dog. Previously she had brought in some Conocybe mushrooms that were poisonous but may or may not have been responsible for her dog getting sick (they are known to contain toxins like the ones in the 'Death Cap' mushrooms but the chemistry of the ones in the Conocybe is such that they have to be absorbed directly into the bloodstream to be harmfull). These turned out to be Collybia fuscopurperea (also called Gymnopis villosypes) an indedible but not known to be poisonous mushroom that is classed by many as a 'LBM' (a 'little brown mushroom' so minute and inedible that its toxicity is inconsequential),

Collybia fuscopurperea



A Beetle Responsible for the Death of An Oak Tree?

 The below beetle and larvae was brought into my office to find out if it was the cause of death of live oak (Quercus agrifolia) here in Arcadia. Turns out this little bugger, called a Nautical borer, chows down on dying and dead oaks but is not responsible for the initial demise of the tree.



Nautical beetle.



Nautical beetle larvae

 What is most probably the cause of the trees demise was evidenced by signs of another, more insidious beetle on an oak tree located nearby. Both branches and trunk of the tree showed the exudate and white sawdust halo of the Polyphagous Shot Hole Borer (PSHB), a fairly new pest that is decimating trees in the area. 

Oak tree branch showing the soaking spot with small sawdust halo inside that is the hallmark of the Polyphagous Shot Hole Borer(PSHB). 

Soaking area on oak tree -a sign of PSHB. 

More on the Nautical borer can be found here: A Field Guide to Insects and Diseases of California Oaks

More on the Polyphagous Shot Hole Borer can be found here:  http://ucanr.edu/sites/socaloakpests/Polyphagous_Shot_Hole_Borer/

Sunflower Leaf Problems

I got the below sunflower leaf from a patron who was worried about weather these symptoms were a death sentence for the sunflower they were found on. This is the sunflower leaf miner, and like most leaf-miners it can be controlled by removing the infested leaves from the plant and cleaning the fallen ones out from underneath the plant. Chemical control is really not necessary unless you are entering the entire plant in a contest and the prize is over $10,000. One good way of keeping damage levels down (besides the above) is to keep fertilization to a minimum. High levels of nitrogen not only make the leaf soft and easy to feed on, but directly feed the leaf-miner with a nutrient that lack of otherwise limits its growth and reproduction. 

Sunflower leaf miner

Columbia London Plane Tree Planted in Temple City

 I was rolling north on Rosemead boulevard and I had to stop the car and take a picture. Why? Because I thought a tree that I really like was being used in a street planting there in Temple City -the Mexican sycamore.  A real good choice by city landscape architects in my opinion; turns out however it was Platanus x acerifolia (Air.) Willd. 'Columbia' planted along side Rosemead blvd. Still a good choice, these hearty trees are more upright, less prone to leaf  problems, and don't drop as many leaves as their native California cousins. It's really nice to see such choice of tree being used on city streets. I can't wait till these  beauties reach their 50 foot maximum height. (Note: I had originally identified the tree as a Mexican sycamore -but found out that it was Platanus 'Columbia' when the city returned my call).

Meet the Bay Suckers

Bay sucker is one of the common names for a psyllid (Trioza alacaris ) that attacks the bay laurel (Laurus nobilis). I just recently had a sample brought to me from a laurel that was infested with these pests. The signs of infestation include distorted foliage and discoloration of the leaves around the distorted areas. This pest is a problem in many parts of the world including Great Brittain. Here the treatment is to prune back the affected foliage and clean up any leaf litter around the base of the tree. It is also a good idea to look at the trees feeding and watering regime. Psyllids and insects like them are fond of soft, nitrogen rich foliage. Laurels growing in shaded areas, receiving to frequent irrigation and especially those that exposed to excess nitrogen (through fertilization and breakdown of too rich compost) are more susceptible to this pest. Once established laurels should not need to be fertilized. It's also a good idea to plant varieties like 'Saratoga' that are resistant to the psyllid. 

Laurus nobilis shoots showing damage from the Bay succker (Trioza alarcis). 

Tour of the Storrier-Stearns Japanese Garden in Pasadena

This month's Plant Information Class was a tour of the Storrier-Stearns Japanese garden; one of the largest private Japanese gardens in the United States. Besides being a gorgeous garden in its own right it is one of the best examples of Japanese garden design in the United States. When you walk through this garden you begin to notice that every 30-50 feet completely new vistas open up, providing an experience where you can feel like you're looking at a different garden wherever you walk. Owner Jim Haddad showed us the garden's 10,000 gallon rainwater recycling system and explained steps the garden was taking to become more sustainable. One of the most interesting things I found out about the garden was Jim's use of Dymondia margaritae, an extremely water saving South African ground cover, as an lawn substitute. We spent almost two hours touring the garden, and could have spent more.

Tea house. 

Terrifying guard-cat. 

Path to the tea house. 

Jim Haddad explains the tea house's finely detailed wooden cut-outs. 

Jim Haddad  talking about the tea house's craftsmanship. 

One of the many fine views; this one from the top of the small hill created when the pond was excavated. 

View looking east; notice the lawn-like area consisting of Dymondia margaretae.

View of the tea house from the north. 

Stone lantern overlooks a peaceful view. 

Class members listen to Jim explaining the construction of  the tea house. 

Interior view of tea house.

Squash growing on compost bin. 

The man-hole covers cap a 10,000 gallon rainwater recycling tank. 

Polyphagous Shothole Borer Susceptible Tree Variety Numbers Growing.

I've been accused of being alarmist about the potential of the Polyphagous Shothole Borer to be a destructive pest here, but it's been pretty alarming. A new paper by Dr. Akif Eskalen and several other researchers has come out detailing the growing number of hosts and trees affected by this pest doesn't do much help. Turns out of all the most planted ornamental trees here in Southern California, over 60% are attacked by the beetle in some way.

Senna tree showing oozing from Polyphagous Shothole Borer  attacks. 

Pretty Looking Leaf Spot on an Ornamental Pear

A local arborist brought this in over the weekend -its Entomosporium leaf spot on an ornamental pear (probably a Bradford pear). It will not kill the tree but if you don't attempt to control it the tree may become weakened from defoliation. The treatment likes in changing the cultural conditions so that the inevitable coating of fine mist that is deposited when our 'June Gloom' overcast layer is really deep and gloomy dries out as quickly as possible, giving the fungi's spores less of a chance to germinate. Besides removing all the infected leaves and disposing of them in the trash (composting them could recycle the spores) this can be achieved by opening up the tree near the base using selective pruning, removing organic  mulches under the canopy of the tree (they keep the moisture levels up too high) and making sure irrigation water isn't hitting the leaves or trunk of the tree. If infestations of Entomosporium are high it's not a bad idea to apply a copper fungicide until the weather gets drier. 

Entomosporium leaf spot on ornamental pear. 

Why Do My Palm Leaves Look Like An Accordion?

The leaves of this palm look like an accordion; why?

Today I came into my office and noticed this waiting for me; the distorted leaf of a king palm with a note placed nearby wondering why the distortion was present. After some research and a discussion with palm expert Dr. Don Hodel (who coincidentally happened to be visiting us today) I have somewhat of an explanation.

The most common reason for this kind of disfigurement on palms is a lack of boron. Essential for the growth of palm trees, boron is fairly common in the soils of Southern California. Even though it is practically ubiquitous there are certain cultural factors that can prevent if from being available to the plant. If the soil is too acidic boron will easily leach out of the soil; one way to do this is to fertilize the lawn surrounding the palm with Ammonium Sulfate, a type of nitrogen source that can acidify the soil its applied to; another way to inadvertently raise the pH would be to keep the area to moist for a period of time -constant moisture and lots of organic material in the soil can lead to an anaerobic and acid condition. But ironically another condition that  can make boron unavailable is soil that is heavy clay and too dry. With the preceding condition the boron becomes bonded to the clay particles and becomes unavailable to the palm.

The first remedy is to find out what physiological or cultural condition is causing the boron deficiency and fix it. Check the drainage around the plant, after a rain or a heavy watering look for water that puddles and doesn't disappear for a while. Check the pH of the soil too with a kit (you can buy these from your local garden center or on the web). Finally, there's the '20 Mule Team Cure'; 2-4 ounces of household borax added to 5 gallons of water for each medium sized palm tree. Make sure to keep the solution agitated because borax doesn't dissolve very easily in water (remember using borax to wash you hands back in the day?).  Err on the side of less rather than more because borax in higher concentrations is an herbicide.

But its not just boron that can cause accordion leaf; anything that adversely affects the main growing point of the palm, the apical meristem, can also cause it as well. This means diseases like pink scale, a fungus that shows up on palms planted in poorly drained areas with poor air circulation, and herbicides can cause the problem too. So make sure to rule out all these causes before you start applying borax to your trees.

Web resources:

Descriptions of boron deficiency:

http://edis.ifas.ufl.edu/pdffiles/EP/EP27300.pdf
http://www.ctahr.hawaii.edu/oc/freepubs/pdf/PD-83.pdf

This document discusses the '20 Mule Team' cure:

http://collier.ifas.ufl.edu/CommHort/CommHortPubs/Boron%20DeficiencyOct05.pdf