I have had a Joseph's Coat climbing rose at my house for over 25 years.  Last year it began looking worn out as if it were on its last legs.  I cut the trunk back almost to the ground and held my breath.  Since I hadn't seen any graft lines, I was hoping that the rose was growing on its own roots and would send up a new cane.

Luckily that is what did happen, and all was right in my gardening world.  Then one day I saw this damage on the leaves and petals.  Now the leaf damage was nothing new.  I knew leaf-cutter bees were the culprits and had made peace with them over the years knowing the damage wouldn't harm the plant.  But I had never seen petal damage before.

I decided to hit the books and see what I could find.  The family of insects that contain leaf-cutter bees is Megachilidae.  Some bee books mention only the genus Megachile as containing leaf-cutter bees.  However, in Field Guide to the Common Bees of California, Gretchen LeBuhn calls the Megachile genus, large leaf-cutter bees, and the genus Osmia, small leaf-cutter bees.  Of note Osmia is also the genus that contains mason bees.  She also mentions several species in the Ashmeadiella genus as being leaf-cutters.

Most leaf-cutter bees tend to appropriate existing long cylindrical spaces as sites for their nests: old beetle tunnels, wall crevices, and large hollow canes or stems.  They then wall these areas off into separate chambers by lining and capping them with leaf or petal material.  The cylindrical cuts you see on leaves is for lining the walls while the circular cut-outs are for capping each segment.  The bee lays an egg in each chamber and places a pollen ball there for the larva to feed on once it has hatched.

Petal damage. photos by Karen Metz

Leaf-cutter bees are excellent pollinators.  They carry pollen in a collection of stiff hairs on their abdomens.  Most other bees carry pollen in special hairs on their hind-legs.

Now with all the damage, I saw on the leaves, I was surprised I had never seen a leaf-cutter bee at work.  But Professor LeBuhn may have provided an explanation.  She noted that it only takes 2-3 seconds for a bee in the Megachile genus to make her cut.  Also, before her job is complete, she has already begun to beat her wings so that she is already flying by the time the cut-out is finished.

Still, at the end of the day, there is still that very visible plant damage to contend with.  I decided to focus on the advice given in California Bees and Blooms which was co-authored by Professor Robin Thorp. “Consider it a good sign that your garden is providing necessary materials for important pollinators nesting nearby.”

Over the years I had gotten used to the leaf damage.  But it was the petal damage this year that really gave me pause.  How could I mentally re-frame the shape of the damaged rose blossom?  I realized that if this shape was on a new variety of dahlia or passionflower, I would think it was very exotic and embrace it.  So, I've decided to embrace it on my rose as well.

photo by David Bellamy

Summer is here and your flowers, vegetables, and weeds are really taking off. It is also the hottest time of year and you may wish to work outside after the sunsets. Now you've got to contend with blood-thirsty summer mosquitos. You may wish you had planted citronella around your garden to help, but does it?

Citronella Grass (Photo: WellspringGardens, Etsy.com)

There are two plants called Citronella. They are Citronella Grass (Cymbopogon nardus or C. winterianus) and Citronella Geranium (Pelargonium 'Citronella'). Citronella Grass, sometimes called Mosquito Grass, is a clump-forming perennial grass, grown as an annual in some colder zones. The oil of these plants can be used as a mosquito or insect repellent and is also used in some soaps and candles. It also has herbal uses and is touted to help with treating lice, intestinal worms, as well as for treating fever or migraines. Think twice about planting this if you have limited garden space since it gets 5-6 feet tall and 3-4 feet wide. Also, just growing it may not repel one “Skeetter”, since the oil in the plant has the repellent properties, and it must be extracted to use. It sometimes called Lemon Grass, and although the two kinds of grass are closely related and look similar, they are two different plants, and only Cymbopogon nardus has the citronella oil.

Although the oil from Citronella grass has been shown to be effective as an ingredient in insect repellent, there are also studies that show no significant improvement. The European Union (EU) has banned Citronella as an insecticide.

Citronella is a natural and organic product and is generally considered safe when used in small amounts on your skin. However, some people have allergic reactions to it. Check with your medical professional before experimenting with it, especially if considering ingesting it or breathing in vapors using the oil. Also, try searching Internet for “is Citronella safe for human use?”

Blooming Citronella Geranium, (Photo: www. Gardenmyths.com/…)

So, you think you'll grow the geranium variety? The citronella geranium has lacy green leaves and purple, pink or white colored blooms. If you just barely brush is as you walk by and you will get a blast of citrus/ floral fragrance. But while they are pretty and pleasantly scented, studies have shown them ineffective in repelling mosquitos. However, having them in your garden may help to cover up the smell of your spray-on insect repellent, so they may still help indirectly to battle the bugs.

Lastly, do Citronella Candles keep mosquitoes away? This is a myth. The amount of oil in candles is extremely small and citronella candles don't work any better than regular candles – neither works well.

https://www.gardeningknowhow.com/ornamental/foliage/citronella-grass/what-is-citronella-grass.htm

https://www.gardenmyths.com/citronella-plant-keeps-mosquitoes-away/

https://www.etsy.com/listing/692558506/citronella-grass-cymbopogon-nardus-live

The Heat is On

Tomatoes Enjoying the Weather

Harvest for the Future

There is a children's book titled Water Bugs and Dragonflies, published in 1982 by Doris Stickney. 

The purpose of this book is to help young children cope with the death of a loved one.  The characters in the book are fun-loving water bugs and dragonflies.

The story portrays the water bugs as a happy little group living below the surface of a quiet pond, playing and working together. However, every once in a while, the water bugs notice one of their members losing interest in the activities.  They watch as a fellow water bug clings to a plant, climbs high up on the plant close to the surface of the water, and then eventually disappears from sight permanently.  They cannot understand where the water bug goes.

So, they come up with a plan.  They decide that the next water bug to climb up the plant must make a promise to return and let them know where they have gone. So, the next water bug climbs up the plant, breaks through the surface of the water, and eventually wakes up on a lily pad.  Upon awakening, he realizes that he now has wings, which he was drying in the sun!  

He flies around a bit and then remembers his promise to the water bugs beneath the water.  He must return and tell them what happened when he left the water.  He can see his buddies under the surface and tries to get back to them to tell them about his beautiful transformation into a dragonfly, but cannot go further than the surface of the water.  He decides that even if he can reach them, they will not recognize him anyway.  He resolves the dilemma by coming to the conclusion that he can still watch over the water bugs, and once the other water bugs become dragonflies, they will all be together again.

When I see dragonflies Anisoptera in the yard, I am often reminded of this sweet children's book and wonder if they are watching over their buddies who are still in the water.  They are so much fun to watch.  Dragonflies hold their beautiful wings open or down.  If you see something that looks like a dragonfly but its wings are held together and upright, this beauty is actually a Damselfly Zygoptera (view pictures below to see the difference). 

In an article written by Betty Victor and published by Solano County's Daily Republic, she noted that there is information showing that dragonflies and damselflies existed in prehistoric times, perhaps even prior to dinosaur existence!

Both the dragonfly and damselfly are quite beneficial, as the nymphs are born and live in the water and feed on mosquito larva.  The dragonfly nymphs are said to look like little alien creatures with a hump hanging on its back.  The damselfly nymphs have narrow bodies, six thin legs, large eyes, and three paddle-shaped gills in the rear. 

Next time you see a dragonfly or damselfly nymph looking up from the water to the surface, perhaps he is looking for his buddy and does not recognize the adult dragonfly or damselfly with the beautiful wings looking over him from above.

Sources

• BUG SQUAD blog and photos by Kathy Keatley Garvey

• Daily Republic “Dragonfiles, damselflies are the ‘good' bugs” by Betty Victor: https://www.dailyrepublic.com/all-dr-news/solano-news/local-features/local-lifestyle-columns/dragonfiles-damselflies-are-the-good-bugs/
• University of California Agriculture & Natural Resources:  ipm.ucanr.edu/