| effects of leaf and sap feeding insects on photosynthetic rates of goldenrod. | herbivory can alter the balance between sources and sinks within a plant, and changes in the source-sink ratio often lead to changes in plant photosynthetic rates. we investigated how feeding by three insect herbivores affected photosynthetic rates and growth of goldenrod (solidago altissima). one, a phloem-sap feeding aphid (uroleucon caligatum), creates an additional sink, and the other two, a leaf-chewing beetle (trirhabda sp.) and a xylem-sap feeding spittlebug (philaenus spumarius) both red ... | 1992 | 28313218 |