This large shrub from northeast Asia has become highly invasive in several regions of east-central states, especially on base-rich soils. Despite the small degree of fragrance in its flowers, this species was initially attractive to the nursery industry. It was also promoted by the USDA for hedging from the 1960s into the 1980s (Luken & Thieret 1996). In Ky. it appears to have been first planted during the 1950s, and it began to spread widely after 1970. L. maackii is now, unfortunately, much more widespread than colls. indicate. Fruits are usually deep red, but rare plants produce only orange fruits (as in L. tatarica). It is likely that the carotenoid pigment in these fruits, rhodoxanthin, causes significant changes in the plumage of some birds that consume large amounts of the fruits (Hudon et al. 2013; and their cited literature). Leaves of maackii contain flavones (apigenin, luteolin), glucoside derivatives, and chlorogenic acid that can have allelopathic effects; apigenin may be most active (Cipollini et al. 2008). Leaf extracts can also reduce the health of amphibian larvae (Watling et al. 2011). Although plants of maackii tend to be less palatable to generalist herbivores than most native congeners (e.g. Lieurance et al. 2015), deer can sometimes reduce invasion by seedlings (e.g. Peebles-Spencer et al. 2018). L. morrowii can also be much browsed by deer (Averill et al. 2016). And during recent years, there has been some indication that a "honeysuckle leaf blight" (Insolibasidium deformans) can reduce growth of maackii, especially on small plants n the open (Boyce 2023) Initial obsrvations suggest that the native Lonicera species may not be seriously affected (M. Eaton, pers. comm., Univ. of Ky.).