Nalu,
Thanks - I thought it might be Japanese beetles. As a child I remember seeing this "lacey" eating pattern on our pansies. However, we would see them during the day in our rural NY state location and pick them off by hand.
Found this website with some interesting suggestions,
http://www.ghorganics.com/JapaneseBeetle.html
See some are listed below.
Japanese Beetle Trap and Bait
The following bait and trap method is to be used during the height of the Japanese Beetle season.
Ingredients:
1 cup water
1/4 cup sugar
1 mashed banana
1 pkg yeast
Dissolve sugar and yeast in the water. Mix the well maxhed banana into the sugar water. Put all ingredients in a gallon milk jug. Place the jug (with the top off) in an area where Japanese Beetles gather. The fermentation and odor of the bait attracts the beetles which get in but not out.
Trap crops for the beetles are African marigold, borage, evening primrose (oonthera), four o'clocks, knotweed, soybeans, white roses, white and pastel zinnias, wild grapes and blackberries.
Nematodes: Another control for the grub stage is to apply beneficial nematodes to the infested area. These are applied at a ratio of 50,000 per square foot of targeted area.
Botanical Control: Pyrethrin, ryania or rotenone. (Not for you of course!)
Bug Juice spray: If you can handle it this is supposed to work. Harvest about 1 cup of beetles, put them in an old blender and liquefy them. Thin this with enough water to make it pass through a sprayer. Spray it on any plants they victimize. NOTE: If you make this out of beetles infected with the milky spore disease you will actually infect more grubs with the disease. So...if you can handle it give it a try!
Susan
Aloha, Angela