I will be examining the percent cover of weeds that will be growing in three sections of my backyard in differing levels of shade, and the rate of how that percent cover increases over time. There is a slightly raised garden bed that I have divided into two sections, drawing an imaginary line straight from the corner of the fence to the wall of the bed, and a third section immediately behind the fence. One section of the bed gets a moderate amount of sun throughout the day, the other gets slightly less overall sun, and the area behind the fence gets a negligible amount of sun. The dividing line separates the garden bed into an east and north side; I have designated the east side as “Area A”, the north side as “Area B” and the area behind the fence as “Area C”. From what I can observe, Area A gets receives sunlight approximately 60-70% of the day, Area B receives sunlight approximately 40-50% of the day, and Area C receives sunlight approximately 10-20% of the day. So far, Area A has the most weed growth, with Areas B and C with very little in comparison.
Pictured are Areas A and B of the overall study area; Area C is behind the fence that is currently in the shade coming from a nearby Douglas Fir. An imaginary line is drawn straight from the corner of the fence to delineate the east side (sunny in picture) and north side (shaded in picture).
Pictured here is Area C, also shaded due to the Douglas Fir – this area is covered by more of its canopy, so it receives very little sun throughout the day. This picture was taken at a time when some sun manages to get through.
Here is a small concentration of weeds on the south side of Area A. These make up the bulk of the overall weed growth in this area.
*Above pictures were taken June 18th, 2024.
This picture was taken on July 25th, 2024. A small tuft of grass has appeared in Area A, which was not present last week.
Based on how things appear to be progressing, I hypothesize that Area A will continue to have the highest percent cover of weeds and will have new weeds grow at the highest rate, and that Area C will have the lowers percent cover and overall growth rate. I estimate that this will primarily be due to Area A receiving the most sun throughout the day, even as the days will progressively get shorter as fall approaches.
Your hypothesis needs to be more general around your piece and your pattern – so weeds and shade. Then your prediction is a bit more specific. Neither should be about area A, B, or C, but high, med, low shade.
Note that your area behind the fence has quite a lot of needles, I think these are probably from the Douglas Fir you measured. Keep in mind in your discussion that this could also be impacting the soil and could be another factor influencing weed growth in this area other than shade.