2019 - fall hive weight and water balance calculator

• graph 1 - dramatic 2019 fall hive weight gain
• graph 2 - flat to decreasing 2018 fall hive weight
• water balance calculator table - 2019 shows a slightly positive fall water balance compared to past years, while 2018 shows a dramatically wet fall water balance

Many factors contribute to fall hive weight gain, but I speculate that that dry conditions favored optimal goldenrod and aster honey bee forage; sadly these dry conditions stressed shrubs and trees.  Local fall water balance appears to slowly cycle with a period of 3 to 4 years, meaning that fall 2020 might also be dry - stay tuned.

flowering trees - June '19

Mostly bumble bees, but a few honey bees are attracted to a flowering sourwood tree. Not shown, flowering mimosa tree which attract pollinators this time of year too. Mimosa have invasive tendencies.  

flowering plants - native or exotic pest

My favorite native flowering plant, spiderwort, attracts a honey bee. Last week, I noticed the unpleasant smell - now I've discovered the privet flowers. Also shown is a bee on a invasive flowering privet .

Another important bee forage are native tulip poplar flowers (not shown) - at this time of year, tulip poplar flower windfalls commonly attract sweet food seeking ants.

2019 spring bloom markers

This Atlanta spring has been like no other year, nor have we ever experienced an average spring.    Yet, I want a rough guide to plan my spring beeyard tasks.   At the moment, hives are in a winter configuration with bee cozy hive wraps and bradford pear and redbud trees blooming.

On February 21st, Atlanta pollen count exceeded 1000 which coincided with a Growing Degree Days (GDD) of 90. I'll use GDD equal to 90 and compare this spring with previous years. I calculated GDD using data from the University of Georgia Automated Weather Network.  I'll also use Julian Day  which converts a MMM-DD-YYYY date format which spans 4 months (January to April) into a seamless day of year format.

In the graph notice:

• similar Day of Year values between this year and 2018
• warm 2017 outlier which reached a GDD equal to 90 on January 19

2018 spring bloom markers

I was hoping to simplify my tracking of spring bloom markers, but instead I added another marker, Growing Degree Days (GDD), which is easy to calculate using free web-based tools.  Julian Day allows me to convert MM-DD-YYYY date format which spans 3 months (February to April) into a seamless day of the year format. GDD is a major convenience, I can tap into a database of daily temperature minimum and maximum instead of recording my own observations.  Focusing on the last two graph points, the accumulated warming this year is roughly 25 days delayed compared to last year (84 versus 59).

Here I compare additional observations with GDD, 1) Acer leaf-out in my backyard and 2) first day that the pollen count exceeds 1000.  Notice how well these markers follow similar graph trends.

Here I show a free web-based tool by AgroClimate which compares this year's GDD to the previous year.  Reading from left-to-right, notice where the curves depart - last year's accumulated warming began in mid January, approximately 30 days earlier than this year.  If the daily high does not exceed 50°F, then the daily contribution to accumulated GDD is zero - the curve does not grow in height. I love this graph layout, but I can't use this tool to go back further in history. This tool can draw the average GDD (not shown), but we all know that no such thing exists in the wild - we have never experienced an average year of weather.

Here I show a free web-based tool by Weather Underground which I used to calculate GDD beyond the previous year in history.  In previous years, I kept the starting point equal to January 1, and I change the ending point in a trial and error manner to achieve a GDD value close to 296.  Why 296 - this is the GDD value where the Atlanta pollen count exceeds 1000 this year.

                     2009 2010 2011 2016 2017 2018 

                      day  day  day  day  day  day

Bradford Pear          65   79   60        56   53
Carpenter Bees         68   87   72        63   77
Acer palmatum leaf out 73   92   77        64   76
Carolina Cherry Laurel 73   97   83        57   76
Pollen Count over 1000                76   51   84
GDD=296 (base 50°F)    92  104   93   84   59   84
Here I show other values that do not appear in the graphs.

tradescantia pallida - three petals and six yellow anthers

While waiting for the light to change on a busy Atlanta street, I saw lots of bees on a patch of tradescantia pallida, also known as purple-heart or purple secretia.  These plants are growing from east facing gaps of a sidewalk wall. 

The bee weight folds the filament at right angle.  Click on the image, it's hard to distinguish between bee's pollen load and the three anthers in her grasp.  Does the recent warm November rain make the filament more flexible? Perhaps these are extra long filaments, I don't know.  In the process of counting petals and anthers I discovered on Wikipedia that this New World plant is part of same genus as my bee friendly plant favorite, spiderwort.

2017 nectar flow

Bee cooperative weather is supporting a strong nectar flow of holly bushes, white clover, spiderwort and tulip poplar. Native mining bees and carpenter bees are extremely active too.

This year, I started to checkerboard the honey cap of over-wintered hives on March 6th. Since then, I check the honey cap every three weeks. My version of checkerboarding uses foundation-less frames with no drawn comb. Yesterday, I added another medium box to each hive. I don't know how long this nectar flow will last, but I have monstrously tall hives.

My swarm capture is drawing comb and growing in size too, but at a much slower pace than over-wintered hives.  

2017 spring markers & honey cap

What feels odd about the first photo?  Maybe it's the expectation that the flowers are larger than bees - not in this case of this holly bush. Here's another prolific flowering tree in the neighborhood - Carolina Cherry Laurel appears in the second photo.

                     2009 2010 2011 2016 2017
                      day  day  day  day  day
Bradford Pear          65   79   60        56
Carpenter Bees         68   87   72        63
Acer palmatum leaf out 73   92   77        64
Carolina Cherry Laurel 73   97   83        57
Pollen Count over 1000                76   51

The point of tracking these day-of-year values is to synchronize my beekeeping practices with spring weather.  The first step/acknowledgement is to admit that there is no such thing as an average year- we have never experienced an average year of weather.  My journal contains spring marker dates which sometimes appear in different months.  So, dates are converted to day-of-year to make the comparison between years easier.  I'm experimenting with comparing first pollen count over 1000.  Pollen count is easy to acquire, loosely correlates with temperature and maybe more objective than my journal notes.

I first saw Steve Page speak at Georgia Beekeepers Association in 2015 on the topic of Sustainable Beekeeping.   Do you want to learn more, sign-up for "It's Time To..." the free email mentoring of Coweta Sustainable Beekeeping.  As Steve is influenced by other beekeepers - so, I'm influenced by Steve and have adapted my beekeeping management which uses Kelly foundationless (F Style) frames.  Last Monday (day 65), I removed the bee cozy and checker-boarded the honey cap of my hives.  

white dutch clover

As ever, this year is like no other year in Atlanta - Lake Lanier is 1.5 feet above full pool.  Atlanta has received lots of rain and many un-sprayed lawns are full of white dutch clover.  It took me many attempts to capture this (cropped) iPhone shot of a honey bee visiting clover.  

Had a quick look in my two hives and they seem to be healthy and with small SHB populations - one hive had one SHB above the inner cover and the other hive had zero - lots of earwigs.  Knock on wood, things look on track for a July harvest and split(s).

three purple petals and six yellow anthers

On the morning walk I discovered honey bees visiting this plant - check out the crisp iPhone photo.   We purchased this flowering perennial too, but I lost track of its name.     I eventually found the plant on an Internet search -  spiderwort.  My garden books were not helpful - perhaps Walter Reeves will consider a Georgia book for beekeepers?

The neighborhood stinks of flowering Privet which started to bloom a few days ago.   A few front yards (without  herbicides) contain tons of white clover.   Has my big honey crop year hit a bump? - is the bee population in or out of sync with the weather and flowering plants? - four inches of rain in three days was ridiculous! - these are the uncertainties of the honey harvest.

bloom calendar / spring markers

                                    2009               2010              2011
                              Day of Year    Day of Year    Day of Year
Bradford Pear                 65                 79                   60
Carpenter Bees              68                 87                   72
Acer palmatum leaf out  73                 92                   77
Flowering Dogwood       80                 93                   80
Asian Wisteria                83                 96                   81
Carolina Cherry Laurel   73                 97                   83

In Atlanta, the arrival of the 2011 spring markers are remarkably similar to 2009.   So, as not to color my 2011 observations, I have intentionally not reviewed my old journal notes......too much.  Picking "the date" for these spring markers requires more patience and discipline than I am always prepared to apply.  Naturally, I want to escape winter and embrace spring.....ticking-off the entire spring marker list during one warm day.   My journal contains spring marker dates which sometimes appear in different months.  So, the dates are converted to day-of-year to make the comparison between years easier.

I speculate that this year, enthusiastic yard clean-up has made it less obvious to spot the arrival of the invasive Asian Wisteria bloom near "my local" coffee shop. My wood deck is a dependable habitat for those territorial wood nibblers (a.k.a. carpenter bees) who emerge/return to same piece of lumber each year.  For example, the carpenter bee arrival are observations only recorded in my backyard....another self imposed rule to my scheme.

cold duration

I tapped into the climate records from the University of Georgia cold duration calculator.  So, it's not just my imagination, but this past winter has been a particularly prolonged cold winter.  This winter our purple heart plant died, but this plant survived the past 5 winters outdoors.

Has prolonged cold temperatures altered when trees bloom or the arrival of other spring markers? My backyard record keeping could be better, but it looks like a ~19 day delay of spring markers when comparing 2010 with 2009.

Bradford Pear              20-MAR-2010    15-FEB-2009    33 day delay 

Carpenter Bees             28-MAR-2010    09-MAR-2009    19 day delay

Acer palmatum leaf out     02-APR-2010    14-MAR-2009    19 day delay

Flowering Dogwood          03-APR-2010    21-MAR-2009    13 day delay

Asian Wisteria             06-APR-2010    24-MAR-2009    13 day delay

Carolina Cherry Laurel     07-APR-2010    14-MAR-2009    24 day delay