Bees love Dandelions

One of our girls enjoying a Dandelion
     It was a beautiful, sunny 15 degree celsius (60 fahrenheit) day in the garden and the bees were very active.  At this time of year there are a wide assortment of blossoms available to be foraged upon but one of the favourites is an unplanted native, invasive plant, the Dandelion (Taraxacum) of the Asteraceae (Aster) Family. Many still think of the Dandelion as an unwanted weed but I hope that attitude is changing along with the need for a manicured lawn.  For us the Dandelion can flower throughout the growing period and if the seed heads are allowed to mature you are guaranteed a plentiful crop.
     My garden is a 4 acre community garden close to downtown Vancouver and through the years I have grown to appreciate the weeds (?) and the invasive plants.  Being a very multicultural city it is so interesting to hear the perspective of different cultures on particular plants.  Gout weed ( Aegopodium podagraria) for example is an extremely invasive plant, native to Eurasia which although enjoyed by the bees is impossible to remove and an irritant to all of the gardeners.  One day two Chinese women approached me and asked if they could harvest our gout weed.  Attempting to hide my enthusiasm I asked them why.  They told me of it's medicinal properties (primarily to treat stomach ailments- thus the name gout weed) and told me how they boil it and prepare a tea.  On the same day I saw two older men harvesting dandelion leaves.  They explained to me that in Italy they cherish the leaves and fry them in olive oil and garlic.  The entire plant is edible and the flower petals, along with other ingredients, are used to make dandelion wine. The leaves are best when they first appear or after the first frost (Recipes). The ground, roasted roots can be used as a caffeine-free dandelion coffee.  Dandelion was also traditionally used to make the traditional British soft drink dandelion and burdock, and is one of the ingredients of root beer.  Also, Dandelions were once delicacies eaten by the Victorian gentry mostly in salads and sandwiches.  Dandelion leaves contain abundant vitamins and minerals, especially vitamins A, C, K, niacin, riboflaven and are good sources of calcium, potassium, iron, manganese and beta carotene.  Lecithin in the flower detoxifies the liver.  As well Dandelions nourish other plants through it's long (up to 3 ft) tap root which brings minerals and nutrients from a less contaminated part of the soil to the surface where it is utilized by the shorter roots of neighbouring plants.  If you break the stem of a dandelion the white fluid that appears can be used to ease the pain of bee stings or sores.  Wow!  What an amazing plant.


     Like us bees are healthier, live longer and perform better when feeding on a mixed diet.  The worldwide practice of monoculture agriculture cannot sustain a honey or native bee population (Hidden Costs of Industrial Agriculture).  In addition this singular diet experienced by bees of professional pollinators causes a weakened immune system and subsequent health issues.

"There is a growing body of evidence showing that poor nutrition can be a major player in affecting honey bee health. Eischen and Graham (2008) demonstrated that well-nourished honey bees are less susceptible to Nosema ceranae than poorly nourished bees.  Naug (2009) tested the hypothesis that nutritional stress due to habitat loss has played a major role in causing CCD by analyzing the land use data in U.S. He showed a significant correlation between the number of colony loss from each state and the state’s ratio of open land relative to its developed land area."   Zachary Huang, Michigan State University

     Bee Friendly Farming practices are essential for a healthy bee population.  Specifically, adopting a 6% diverse pollinator beneficial planting farming practice.  Different pollens have different nutritional value to bees and studies have shown a slight improvement in performance when feeding on Dandelion (Nutritional Value of Bee Collected Pollens).  Interestingly for me two of the best pollens for bees, blackberry and cottonwood are aggressive volunteers in our garden.


     Although the plum and flowering cherry blossoms are finished for us there is an amazing number of plants coming into blossom like the apple, pear, cherry, bulbs, purple deadnettle and marsh marigold.  Also, today was the first day I saw Raspberry flower formation which for us is the major bee forage in May through June.
     Please put away the Roundup and let your Dandelions grow.  You can control the spread of the plant by removing the flowers before they go to seed (Dandelion Wine ?).  Your bees will thank you.


Charles Darwin and the Bumblebee (Humble Bee)

 
     This quote from Charles Darwin is applicable to present day bees.  Bees have a very weak immune system and are not very adaptive to environmental changes caused by us.  Global warming and the increased presence of agrichemical toxins are conditions many species of bees will not survive. Their extinction will effect others species dependent on their pollination.
     I think like many of us Charles had a special place in his heart for Bumble Bees or Humble Bees as they were known prior to World War I.  With the help of 5 or 6 of his children between the years 1854-1861 Charles made a number of recorded observations on the flight routes of male Humble Bees (Charles Darwin on the routes of male Humble Bees).  In the first edition of "On the Origin of the Species" by Charles Darwin (1859) he describes how essential Bumble Bees are for the pollination of plants and specifically the red clover (Trifolium pratense).  This he explains is because of it's unique ability to reach the nectar which eludes other bees. (Different pollinators for different plants)

     "Charles Darwin wrote of "humble-bees"... "plants and animals, most remote in the scale of nature, are bound together by a web of complex relations. [...] I have [...] reason to believe that humble-bees are indispensable to the fertilisation of the heartsease (Viola tricolor), for other bees do not visit this flower. From experiments which I have tried, I have found that the visits of bees, if not indispensable, are at least highly beneficial to the fertilisation of our clovers; but humble-bees alone visit the common red clover (Trifolium pratense), as other bees cannot reach the nectar. Hence I have very little doubt, that if the whole genus of humble-bees became extinct or very rare in England, the heartsease and red clover would become very rare, or wholly disappear. The number of humble-bees in any district depends in a great degree on the number of field-mice, which destroy their combs and nests; and Mr. H. Newman, who has long attended to the habits of humble-bees, believes that 'more than two thirds of them are thus destroyed all over England.' Now the number of mice is largely dependent, as every one knows, on the number of cats; and Mr. Newman says, 'Near villages and small towns I have found the nests of humble-bees more numerous than elsewhere, which I attribute to the number of cats that destroy the mice.' Hence it is quite credible that the presence of a feline animal in large numbers in a district might determine, through the intervention first of mice and then of bees, the frequency of certain flowers in that district!" (from Chapter 3 "On the Origin of the Species").
     A logical extension made in jest by Thomas Henry Huxley (Huxley, 1892) was " that old maids keep cats, and by unknown others to include the concepts that the economy of the British Empire
was based on roast beef eaten by its soldiers, and cattle rely on clover, so as to conclude that the prosperity of the British Empire was thus dependant on its population of old maids." (Charles Darwin, Humble Bees, Clover and Cats).
     
  Bombus pascuorum (Common Carder-bee) on red clover

     As most bumblebees are ground dwellers their existence depends upon the population of nest destroying mice whose population depends on the subsequent population of predatory cats.  Therefore, the greater the population of cats the greater the number of bumblebees and the greater the pollination of red clover.  We must also consider the negative effect of cat predation on birds, amphibians and reptiles.  This is why an ecosystem functioning in equilibrium (balanced populations) is so important.
     In May of 1858 with the aid of a beekeeper Darwin carried out studies on honey bee cell building at his home in Kent, England.  "For people to accept his theory of evolution by natural selection Darwin knew that he had to explain how the hexagonal cells found in the wax of the beehive were fortified by natural processes.  As a result of his observations he concluded that the hexagonal shape is produced as a result of spherical cells touching each other and the bees using the minimum amount of wax possible.  The experiments are described in "On the Origin of the Species".

 
     The family home of Charles Darwin is wonderfully preserved in Kent and is much the same as it was in the 19th century when he and his children carried out their observations of both the honey and humble bee.

   
 
     Due to habitat loss and the use of agrichemicals many species of Humble Bees are endangered.  In Britain the Bumble Bee Conservation Trust is working to save the Humble Bees.  In North American join Bumble Bee Watch to help endangered species of Humble Bees.

Left Bombus Mixtus (Male) and right Bomus Caliginosus or Bombus Vosnesenskii on a sunflower at Cottonwood Garden

My favorite an Orange Rumped Humble Bee (Bombus melanopygus) enjoying a cranesbill geranium at Cottonwood Garden

Another Humble Bee beautifying Cottonwood Garden