Natural navigation is at its most fun when it is a puzzle and a test of our senses. Have a look at this photo and get ready to test your powers of observation.
This is a photo of a monkey puzzle tree that I have been growing in our greenhouse since early this year. I have taken it out of the greenhouse for better light for this photo. Greenhouses are great places to study the effect of sunlight on plant growth because all the wind effects are cancelled.
Now see if you can tell in which direction this photo was taken. Are we looking north, south, east or west?
In this photo we are looking west. The monkey puzzle tree has grown towards the southern light to the left, an effect known as ‘phototropism’.
‘That’s easy!’ I hear some of you cry, but I did warn you that this was a test of your powers of observation. What I did not tell you is there were two marks on offer.
Now be honest, did you spot the way there is more moss growing on the southern side of the soil too? The sunlight cannot reach the left, southern side of the soil because it is being blocked by the rim of the flowerpot. (Those of you already familiar with natural navigation will be aware that this is the same shading effect that leads to more puddles on the southern side of east-west tracks).
And no, before you ask, there is no bonus point for spotting that the chicken is aligned east-west in the background.