Honeybee NectarFlow-Black Locust Trees

Black Locust bloom

Planting peas by St Patrick’s Day is an American farming tradition that goes way back and I can remember my father relating this age-old practice. He spent his childhood on a farm and knew all the old-time ways. I didn’t have any beekeeping relatives, but if I had I am sure they would have told me to super my hives (adding extra storage boxes for nectar) when the Black Locust blooms. Beekeepers, like farmers, still look outside in the natural world to gauge how to manage their honey crop.

The lower large box is a brood box, where the queen lays eggs, and the upper boxes are supers

The Black Locust tree, Robinia pseudoacacia, is famous for producing a fruity and fragrant light green honey. Native to the Eastern United State, I always look for this tree to bloom in the spring as a sign that “honeyflow” or “nectarflow” is starting for my honeybees.

Honeybees love native Black Cherries that bloom at the same time

An abundance of nectar sources blooming in profusion means a nectarflow is starting with the bees collecting excess nectar. When bees bring in more nectar than they need or can use, that is when a beekeeper rejoices and can remove the extra stored honey for themselves. Contrary to widely held opinion, bees only produce excess honey in the early spring or occasionally in late summer, and beekeepers harvest in July for much of the United States. In southern states, where native flowering is much more abundant over a longer time period, beekeepers can get two harvests.

Honeybee nectaring from a late nectar source-Dahlia

The Black Locust tree is native to eastern and southeastern North America, but has spread throughout the United States and much of Canada and can be invasive. They grow quickly on roadsides and fields and now the creamy heavily scented branches are hanging heavy over a road that I travel every day. Most people would zip by and not pay any attention at all to these beautiful trees as the blooms are usually high up in the canopy. But I stop and whip out my camera to zoom in on these beautiful blossoms!

The flower racemes pull down the branches of the tree

Last year, because of the fickle weather, Black Locust didn’t bloom in the great abundance that I see this year, so I am hoping for a good honey harvest. But this spring we have had lots of spells of rainy cold days when the bees can’t fly and that might cut short the nectar flow.

A warm and sunny spell during honey flow means that a strong hive can fill a honey super with nectar in two days! Remember…. that is nectar. Ripe honey has had its water fraction reduced greatly by bees fanning nectar to increase water evaporation to produce the sugar concentration necessary to produce honey. Once honey is ready, the bees cap over the top with wax.

Ripe honey cells are capped by wax in the upper left hand side; on the lower right are growing brood

Blooming for about 10 days between April and June, here in the mid-Atlantic, the racemes of blooms of Black Locust opened in early May. Even before the flowers opened, the bees started collecting pollen from the tree which they need to feed their growing brood or larvae. Worker bees will flock to the flowers for the abundance of nectar that they produce, once the days turn warm and sunny and browse from other flowering trees and vegetation, like the Black Cherry. With the onset of blooming, bees start producing wax which requires several times more nectar than honey. And bees need honeycomb built first before storing nectar. The purpose of a spring flow, for the bees, is to provide food for the rest of the year, not honey for the beekeeper!

The racemes of the Black Locust flowers hang down 8 inches

After this big burst of native bloom, there is usually a summer dearth until goldenrod, asters, and other late bloomers appear. That is why gardeners should plant summer bloomers to supplement their diet. Plant those Zinnias, Sunflowers, etc. Go to Plant These For The Bees.

Plant These For The Bees poster available at TheGardenDiaries Etsy Shop

Asters are an important late season nectar source for all pollinators

Healthy hives may produce queen cells in preparation for swarming, as the spring nectarflow builds; their normal method of making new colonies. The old queen and a large swarm of bees will go off and begin a new hive. See Swarming of the Bees.

Producing more queens prior to swarming
Bee swarm in my backyard tree

Interesting and Surprising Facts About Black Locust

  • Abraham Lincoln, as a young man, built up his muscles splitting logs from Black Locust trees for firewood and fence posts

  • Extremely hard wood, one of the hardest and rot resistant in North America, the wood is valuable for floors, boats, fence posts, and furniture

  • A member of the Fabaceae (pea family), the tree has nodules of nitrogen-fixing bacteria on its roots which make it an excellent species for re-vegetating poor or damaged soils

  • Newly cut wood has an offensive odor which disappears with time

  • The flowers are eaten in Japan, France, and Italy, battered and fried as beignets or in tempura

  • The bark, wood, and leaves are toxic to livestock and humans, so farmers remove them from their fields

  • Black Locust blooms along with privet, multi-flora, blackberries, honeysuckle, and other native vegetation to produce the abundance of available nectar for pollinators; so even invasives play a role in supporting pollinators

  • Black locust is an interesting example of how one plant is considered an invasive species even on the same continent it is native to

  • Racemes of flowers can hang 4-8 inches long and intensely fragrant smelling like an orange tree

  • Highly tolerant of pollution, the tree is planted in Europe and produces the acclaimed ‘Acacia Honey’

  • One of the best woods for burning in wood stove, it has little or no flame and can burn when wet, burning at a comparable temperature as coal

  • Compounds in the heartwood allow the wood to last over 100 years in soil

 

 

 

 

Native vs Non-Native-Which is Better for Pollinators?

butterfly
Tithonia, Mexican Sunflower, native to Mexico and Central America, is one of the top insect drawing plants in my garden

Native Vs Non-Native

Native or non-native in the garden: Which is better? Simple- everyone knows the answer to that question…Natives of course! As gardeners, we have been bombarded with information about the value to wildlife of native plants and the more natives the better. But the definition of natives has always been fuzzy to me. Are natives plants that originated within our region, state, or North America? Or things that predate Europeans settling North America? Or does it mean plants indigenous to a particular habitat or ecosystem? And how about cultivars of native plants-like different varieties of Anise Hyssop which is a North American native? There are no easy answers to these questions.

070
‘Pink Panther’ Anise Hyssop is a bee magnet
DSCN1921
Liatris is a great native wildflower that I grow for bee value

I have always been skeptical about the native plant zeal and ready to challenge it after my observations of over 50 years of gardening experience. My blog post on the benefits of planting Butterfly Bushes stirred up some controversy. I acknowledge that Butterfly Bush provides only nectar and not foliage value to caterpillars as a host plant. But I still urge people to plant Butterfly Bush because deer won’t touch it and the butterflies flock to it and I enjoy the plant for its beauty and ease of growth. There aren’t many flowering shrubs that deer leave alone which makes it valuable as a landscape plant.

IMG_9271
Pipevine Swallowtail on Butterfly Bush flower

I always deferred to the experts about native plants because anecdotal evidence is not the same as peer reviewed scientific articles.  So, I had no numbers to back up my belief gained from experience. Planting a diverse assortment of flowers- be it perennials, vines, annuals, trees, or shrubs or native and non-native to provide a healthy and beautiful habitat was always what I have practiced. My decisions on what to plant was determined by whether the plant was appropriate for the location and environment, not fussy, and that it wasn’t invasive.  Invasive means that a plant is spreading prolifically and undesirable or harmful to the habitat.

P1060383
A roadside field of invasive Purple Loosestrife,, Lythrum salicaria, originally from Europe
P1060381
Invasive Japanese Beetles feeding on Lythrum

Plants For Bugs Article

My longtime observations of planting a diverse selection of plants, both native and non-native, was recently backed up by an article, “Plants For Bugs: all in the mix” by Helen Bostock, who is a RHS Senior Horticultural advisor, from across the pond. Bostock says the average UK garden contains around 70 percent non-native and 30 percent native plants. I couldn’t find the U.S average, but I think it is probably very close to that same percentage. Bostock concludes that native use is on the rise, especially with the ‘back to the wild’ environmental movement, and ongoing education of home consumers of landscapes. I see it happening in my own practice of landscape designer with more and more requests for butterfly/wildlife friendly landscapes and less requests for manicured formal gardens. Gardens are still very unlike natural habitats but have a much greater diversity of plant species than their surroundings which have been degraded with development encroachment.

Disney wedding 163
Zinnias are not native to my area but pollinators love them

Bostock’s research concludes after studies spanning four years that a mix of plants from around the world may be the most effective way to sustain pollinators. This was no surprise to me. The native bandwagon has acquired mystical connotations in the past 10 years and claims that natives use less water, are disease free, and low maintenance have been made over and over.

P1060243
I am slowly removing turf and planting meadows with native plants on my property

But what role do garden plants (both native and non-native) play in supporting wildlife?  Views differ on whether planting native plants only is necessary for the most wildlife friendly garden. This was the question posed by the Wildlife Gardening Forum in the UK and they set up a field experiment designed to test whether the geographical origin of a plant affects the numbers and diversity of insects and other wildlife.

024 (3)
Pollinating fly on mint flower

Conclusions

This is what the RHS study has concluded:

• Research reveals a mixture of native and non-native ornamental plants may provide the best resources for pollinating insects in gardens
• Native plants are not always the first choice for pollinators visiting gardens
• Non-native plants can prolong the flowering season providing an additional food source

Surprising results for many!

The basis of a garden’s health and vigor is determined by invertebrates, animals lacking a backbone. The more critters making a home or just stopping by for a refueling visit, the healthier your garden is to the environment and your health and well being.

P1050823
Dragonfly on waterlily

 Findings and Messages

For all pollinator groups on all treatments, greater floral resource, either native or non-native, resulted in an increase in visits. There was, however, a greater abundance of total pollinators recorded on native and near-native treatments compared with the exotic plots.

P1060158
Allegheny Vine, Adlumia Fungosa, is an endangered North American native, closely related to Bleeding Heart

Exotics were notable in extending the period of bloom which is really important to attract insects all season long.

The takeaway here – use site appropriate native plants when possible, understanding that some are a bit more boisterous than others, but add exotics where appropriate to enrich and extend the season. Gardens can be enhanced as a habitat by planting a variety of flowering plants, tilted towards native and near-native species.

 

The Great Butterfly Bush Debate

Butterfly on butterfly bush bloom
Butterfly on butterfly bush bloom

Butterfly Bush, Buddleia davidii, has been widely bashed from garden writers, ecologists, and conservationists. Attacked from all sides by master gardeners and other garden professionals, I am sticking to my guns on the benefits and pleasures of planting it. “An invasive thug that only provides sugar-water”: That is the complaint that conservationists use to discourage you from planting this shrub.

Swallowtail
Swallowtail

 As a preferred late summer nectar source and butterfly magnet, I enthusiastically promote it in my butterfly presentations for its many virtues. An important tool to draw butterflies, I also plant many natives next to it that can act as host plants.

Swallowtail on bloom
Swallowtail on bloom

One of the few flowering shrubs that deer will not touch, I use it all the time in my landscape designs as an easy to grow, beautiful, fragrant, disease free, flowering shrub. The only care required is a general whacking back of the whole shrub in the early spring to encourage bushiness and flower production. Over 100 varieties provide a wide palette of forms, sizes, and colors, to choose from. The dwarf varieties are especially valuable for small gardens and containers, like ‘Blue Chip’ and ‘Pink Chip’, growing only 4 feet tall.

Butterfly Bush 'Pink Chip'
Butterfly Bush ‘Pink Chip’

Why do butterflies love this plant? Providing loads of sugar water , the nectar filled nectaries, are shallow which is important to accommodate the short-tongued butterfly. Butterflies can reach the copious nectar easily which has a high percentage of sucrose, an energy fuel. Attractive to moths, bees, and other insects, this plant is valuable to all kinds of wildlife, not just butterflies.

Miss Molly Butterfly Bush in border
Miss Molly Butterfly Bush in border
Miss Molly adds a new color, raspberry, to the mix
Miss Molly adds a new color, raspberry, to the mix

Native to Japan and China, butterflies don’t care where their source of nectar hails from. In my post Butterfly Watching, I noted that butterflies have taste receptors on their feet to locate food and if their foot’s receptor and the molecule match, the butterfly eats. So, the plant’s origin is irrelevant and is an attractive food source. As humans, we eat many non-native plants, why can’t a butterfly do the same?

The butterfly bloom nectaries are numerous and easily accessible
The butterfly bloom nectaries are easily accessible

Invasive thug or non-native adaptive? There are several ways of looking at this plant. I know that it invades into mostly disturbed areas where lots of aliens/invasives have already taken over and is known as an invasive in over 25 states. But still, it is providing an important late summer source, when it is sorely needed. The other short-coming that ecologists claim is that butterfly bush only provides nectar, not acting as a host plant for the caterpillar to reproduce, but that is also true of other native plants.

Monarch caterpillar on milkweed
Monarch caterpillar on milkweed

Butterfly Bush seeds do not ripen until dry weather during the following spring. Worried by the potential for invasiveness? Then you can dead head it before the seeds ripen in the spring or cut the whole bush back which will eliminate the spread of seeds into adjacent habitat. Colonizing disturbed ground sites such as railway lines, quarries, roadsides and waste ground, butterfly bush can form dense stands of shrubs that butterflies flock to. What’s not to like!? Here is the position of the UK’s Butterfly Conservation on their website:

“Buddleia provides an important nectar source for adult butterflies, moths and other insects in townscapes and the countryside. This has become increasingly relevant because wildflowers have become so depleted following habitat loss and the general lack of nectar sources in the countryside. It also brings enjoyment to many people, both because of its heavy-scented and beautiful blooms but also because of the butterflies and other insects it attracts. It therefore plays a role, alongside other non-native garden plants, in helping to maintain or restore the link between people and native UK wildlife such as butterflies. In gardens, Buddleia is often pruned annually thus removing seed-heads and reducing the potential for seeding.

Buddleia is not important as a caterpillar food-plant and cannot replace naturally occurring wildflowers, which are crucial to provide a variety of nectar through the year as well as being food-plants for caterpillars. Buddleia can cause serious problems on some important conservation sites, especially brownfield sites. It needs to be controlled in these and other semi-natural sites to allow natural vegetation to develop. The cost of control can sometimes be considerable.

In reaching a position on Buddleia it is important to weigh up the undoubted benefits it brings in garden situations against the possible risks to wildlife habitats. It is also important to recognise that Buddleia is already naturalised and well established across much of the UK.

In view of its value as a nectar source, BC will continue to recommend its planting in gardens alongside other butterfly-friendly non-native plants, but will avoid giving it undue prominence and will give advice on its management and control.

Miss Molly
Miss Molly

A sea change is going on with some conservationists, that we are dealing with a changed world and there is no way to go back to an idealized world of  stable co-habitating species. From the beginning of time, species have moved around, finding new territories, and creating new ecological niches. Invasive species, like it or not, are part of nature. Serving an ecological purpose, whether it aligns with our idea of what it should look like, isn’t relevant to nature.

And according to the Royal Horticultural Society:

• Research reveals a mixture of native and non-native ornamental plants may provide the best resources for pollinating insects in gardens
• Native plants are not always the first choice for pollinators visiting gardens
• Non-native plants can prolong the flowering season providing an additional food source.

So, armed with this knowledge, you make the decision.

Swallowtail on bloom
Swallowtail on bloom