Japanese Beetle Blues 2016

Unlike welcoming the lazy days of summer, unwelcome Japanese beetles have emerged to begin their two month feeding frenzy. Their appearance is about three weeks earlier than last summer.  Maybe that means they'll die off three weeks earlier, doubtful.  My hunch is the numbers will be fairly numerous in my area and they will probably find new neighborhoods to torment. 

I wrote four blogs about them last summer, so for repetitive sake, click here to read - Japanese beetles.  This is the link to the fall blog, but a good place to start (backwards), plus all the links to my earlier blogs.  

In a nutshell, they are beyond annoying insects, they skeletonize foliage and flowers of many of our favorite landscape plants. They live for only three reasons - to screw, chew and destroy! 

Control sprays may not be 100% effective, so hand pick or flick reachable JBs into soapy water and toss dead contents often, they start to smell after a few days. Stay on top of removal because if you don't, more will arrive to join in their party feast. Commercial or homemade traps aren't recommended either.  They catch lots of beetles, but they signal more to the area.

 
I mentioned controls in my earlier blogs, but one product, a very environmentally safe product Btg is totally sold out from mail order companies until later in the summer. 

Check out Dr. Cranshaw's Colorado State University fact sheet for more information and controls for Colorado - Japanese beetle Fact Sheet 5.601



Check out my July 2, 2016 Denver Post Punch List - Tips for Fighting Japanese Beetles  

This chart on plants they favor or mostly avoid is compiled to the best of my knowledge from reliable university and government fact-based websites.  

Trees/Shrubs JB Favor	Trees/Shrubs JB Do Not Favor	Perennials JB Favor	Perennials JB Do Not Favor
American and English Elm	Arborvitae	Grape	Hellebore
Birch	Boxelder	Hollyhock	Iris
Black Walnut	Boxwood	Rose	Liatris
Hawthorn	Dogwood	Raspberry	Lily
Horse Chestnut	Euonymus (burning bush)	Virginia Creeper	Columbine
Norway Maple	Forsythia	Silver Lace Vines	Lily-of-the-Valley
Larch	Holly	Hibiscus	Coreopsis
Linden	Juniper	Common Mallow (weed)	Larkspur
London Planetree	Lilac (Common)	Evening Primrose	California Poppy
Malus spp. (crabapple, apple, etc.)	Magnolia	Clematis	Foxglove
Mountain Ash	Mulberry	Peony	Coral Bells
Pin Oak	Northern Red Oak	Joe Pye Weed	Hosta
Pussywillow	Pine	St. John’s Wort	Impatiens
Prunus (flowering cherry, etc.)	Red and Silver Maples	Coneflowers
Beech	Redbud	Hops	Forget-me-knot
Rose of Sharon	Spruce		Pachysandra
Rose	Sweet Gum		Poppy
	Tulip tree		Moss Rose
	Yew		Sedum
			Yarrow
			Milkweed and Butterfly Weed
			Aster
			Baptisia
			White Mums
			Dianthus
			Bleeding Heart
			Gallardia
			Geum
			Baby’s Breath
			English Ivy
			Beebalm
			Obedient Plant
			Spiderwort
			Veronica

Annuals/Vegetables/Herbs JB Favor	Annuals/Vegetables/Herbs JB Do Not Favor
Cannas	Begonias
Gladiolus	Caladiums
Sunflower	Dusty Miller
Morning Glory	Ageratum
Cardinal Flower	Lantana
Zinnia	Nasturtium
Anemone	Violet/Pansy
Dahlia	White Geranium
Sweet Potato Vine (seem to like darker varieties) in my garden	Snap Dragons
Asparagus	Cosmos
Rhubarb	Ornamental Kale
Green Beans	Nicotiana
Soybeans	Ornamental Pepper
Sweet Corn	Petunia
Strawberries	Portulaca
	Verbena
	Garlic
	Rue
	Tansy
	Catnip
	Chives
	Leeks
	Onions
	Tomatoes