Answer: Asclepias, or milkweeds, attract butterflies. The yellow dots on the tops of your plants could be eggs, not insects. If you're sure they're moving (use a magnifying glass to make sure), you can first try washing them off with plain water. If that doesn't work, insecticidal soap is effective against soft-bodied insects such as aphids. Aphids come in all colors, from pale yellow to green to black, and shades in between. In a diverse garden, where there are aphids there are likely to be ladybugs. Ladybug eggs are a yellowish orange in color and are laid in clusters. When the eggs hatch, the hungry larvae look for aphids. So, before spraying anything, make sure you've positively identified the problem as a pest.
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