Friday, July 28, 2017

The Cost of Sex

Date published: 2017, July 28
Source material: 2017, April-July

          In the course of my biology education, the cost of sex and reproduction to an organism has repeatedly come up across specialties - and plant sex is no different in the relevance of the notion. For mammals, females usually carry most of the energetic burden due to long gestation and lactation periods relative to other animals. However, sometimes males in the animal kingdom also pay a cost to pass on their genes. For example, a male walrus in "rut" undergoes a reproductively active period of a few months, where the walrus directs massive amounts of energy to its sole focus of reproducing and vocalizing for potential mates. During this period, male walruses can lose their coat of brown fur, have increased disease susceptibility, and their eyes start to turn red and bulge out as an odd indicator of systemic bodily neglect. There is also the famous example of a praying mantis male literally sacrificing itself to offer nutrients to the mom and in turn, increases the fitness of his offspring. The aptly named black widow spider undergoes a similar ritual.
          With such examples in mind, it should come at no surprise that all those flowers in last month's blog post, Spring at Elandan Gardens, have a cost to those trees too. The trees' hard-earned sugars and nutrients were spent in exchange for beauty, pollen generation, pollinator attraction, wind pollination (for less showy trees with cones, most maples, etc.), and seed maturation. For a healthy tree, these expenses are not a problem, but we may still have reason to intervene and choose whether to allow our bonsai to reproduce or not. I will demonstrate some examples of how one might acknowledge the energetic cost of plant reproduction and control it as a tool to speed development, increase health, or maintain the balance of vigor of your bonsai.

1. For Trunk Development
2. For Recovery
3. For Disease Resistance
4. Final Thoughts and Tips

One of Dan's Azaleas covered with flowers and reproductive energy.