Native milkweed cultivars planted by the public can support monarch butterflies and bees

October 07, 2020

Plant cultivars are natural variants of native plants that have been deliberately collected, selected, cross-bred or hybridized for desirable traits that can be maintained through propagation. Although experts generally discourage using cultivars for ecological restoration in natural habitats such as forests and wetlands, consumers find them attractive when seeking new plants that combine the attributes of natives and ornamentals. For the nursery industry, cultivars open the door to new introductions and vast market potential. Indeed, most native plants sold at most garden centers are available only as cultivars as opposed to true or ''wild type'' native species.

Researchers Adam Baker and Daniel Potter from the University of Kentucky College of Agriculture, Food and Environment set out to study whether or not native milkweed cultivars, planted by 'citizen ecologists', were effective in helping to support the declining monarch butterfly populations.

"Native milkweed cultivars including those selected for novel floral display, longer blooming duration, compact growth form and other consumer-attractive traits are increasingly available in wholesale nurseries and at local garden centers," said Baker. "It is important to determine whether these cultivars have the same ability as wild-type native plants to attract monarchs and bees and contribute to effective ecological gardens."

In the study, Baker, Potter and their collaborators planted six urban gardens each containing two species of native wild-type milkweeds (swamp and butterfly), along with three cultivars of each species. They monitored them for monarch and bee visitation for two summers. In both years, monarchs laid many more eggs on swamp milkweed than on butterfly milkweed, despite both species being equally suitable food for the caterpillars. Importantly, in both milkweed species, they found the native cultivars were just as attractive and suitable for monarchs as the respective wild-type counterparts from which those cultivars were derived.

"Previous research has shown that monarch butterflies tend to lay more eggs on taller milkweeds than on shorter ones," Potter said. "We think that is what has happened in our study because swamp milkweed is significantly taller than butterfly milkweed, and probably easier for the egg-laying female monarchs to find."

Milkweeds produce a lot of nectar, so besides monarchs they also attract and help to sustain native bees, honeybees, various butterflies and many other nectar-feeding insects. In the study, the scientists identified more than 2,400 bees, representing five bee families and 17 genera, visiting the milkweeds while they were in bloom. They found that swamp milkweed and its cultivars attracted proportionately more large bees, including bumble bees, carpenter bees, and honeybees, whereas butterfly milkweeds attract proportionately more small native bees. Importantly, within each native milkweed species, the cultivars attracted similar bees as their native counterparts.

These findings suggest that the efforts of individual gardeners to plant milkweed, either wild-type native plants or native cultivars, can be helpful in supporting the declining populations of both monarch butterflies and other insects.


Related Butterflies Articles from Brightsurf:

Two centuries of Monarch butterflies show evolution of wing length
North America's beloved Monarch butterflies are known for their annual, multi-generation migrations in which individual insects can fly for thousands of miles.

Vagabonding female butterflies weigh in on reproductive strategies
A new study by researchers from the National Centre for Biological Sciences (NCBS), Bengaluru, published today in the Royal Society's journal Biology Letters, shows that dispersals, when undertaken by butterflies in search of unpredictable resources, selectively burden the egg-carrying females on their long flights.

Migration and dispersal of butterflies have contrasting effect on flight morphology
Migration and dispersal are vastly different activities with very different benefits and risks.

Scientists unravel the evolution and relationships for all European butterflies in a first
For the first time, a complete time-calibrated phylogeny for a large group of invertebrates is published for an entire continent.

Human handling stresses young monarch butterflies
People handle monarch butterflies. A lot. Every year thousands of monarch butterflies are caught, tagged and released during their fall migration by citizen scientists helping to track their movements.

What do soap bubbles and butterflies have in common?
A unique butterfly breeding experiment gave UC Berkeley researchers an opportunity to study the physical and genetic changes underlying the evolution of structural color, responsible for butterflies' iridescent purples, blues and greens.

Bacteria get free lunch with butterflies and dragonflies
Recent work from Deepa Agashe's group at NCBS has found that unlike other insects, neither butterflies nor dragonflies seem to have evolved strong mutualisms with their bacterial guests.

How some butterflies developed the ability to change their eyespot size
New insight on how a butterfly species developed the ability to adjust its wing eyespot size in response to temperature has been published today in eLife.

Butterflies can acquire new scent preferences and pass these on to their offspring
Two studies from the National University of Singapore demonstrate that insects can learn from their previous experiences and adjust their future behaviour for survival and reproduction.

Beating the heat in the living wings of butterflies
Columbia engineers and Harvard biologists discover that butterflies have specialized behaviors and wing scales to protect the living parts of their wings.

Read More: Butterflies News and Butterflies Current Events is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to