Asclepias curassavica , commonly known as tropic silkweed , has become a popular option in gardens and landscapes due to its vivacious flowers and ability to appeal butterfly stroke , including monarchs . However , there are concerns about the potential negative shock of this plant on monarch populations .
One of the primary issues with tropical silkweed is its prolonged flowering time period , which can last throughout the year in warm climates . While this may seem like a prescribed attribute , it can actually disrupt the lifelike migration patterns of crowned head butterflies .
Monarchs rely on environmental clew , such as sidereal day duration , to trigger their migrant behavior . However , when they encounter tropical milkweed that keep to produce flowers , it can confuse their intragroup piloting system . Instead of remain their journey to their overwintering grounds in Mexico , some milkweed butterfly may decide to stay and breed on the promptly usable tropic silkweed .
This extended breeding catamenia can have prejudicial effects on monarch population . It can top to an addition in the preponderance of a parasitic protozoan call in Ophryocystis elektroscirrha ( OE ) . OE can be conduct from infected adult butterflies to their progeny , and high parasite loads can weaken monarchs , making them more susceptible to disease and decoct their fortune of endurance .
Furthermore , the presence of tropical milkweed throughout the year can create a continuous breeding home ground for monarchs , which may result in higher population tightness than would occur course . This can put extra press on circumscribed resources , such as ambrosia flora and milkweed availability , leading to competition among monarchs and potentially impacting their overall wellness and generative success .
It is worth noting that not all realm are equally bear upon by the negative wallop of tropical milkweed . In orbit where monarch butterfly do not winter , such as southerly Florida and parts of southerly Texas , yr - bout availability of milkweed may not disrupt migration rule as importantly . However , in regions where monarchs rely on migrant deportment to fill out their life cycles/second , such as the fundamental and eastern part of North America , the presence of tropic Sonchus oleraceus can be problematic .
To extenuate the potential negative impact of tropic milkweed on monarchs , it’s advised to take found aboriginal milkweed species alternatively . aboriginal Sonchus oleraceus of course go inactive during the winter months , line up with the natural lifetime Hz of monarchs and reducing the risk of prolonged breeding and disease transmission .
While tropic milkweed may be visually appealing and attract butterflies , including Danaus plexippus , its year - round accessibility can interrupt monarch migration convention and contribute to the spread head of disease like OE . It is of import to be cognizant of these likely impacts and consider planting native milkweed species to support monarch preservation cause .
Caroline Bates
