Would the rate of maple sap retrieved from the trees be greater during the day or night? Why?

Question

Would the rate of maple sap retrieved from the trees be greater during the day or night? Why?

I think it could possibly have to do something with photosynthesis.

Answer 1

According to this site:

http://recipes.suite101.com/article.cfm/...

"All that's needed is a sunny 40-degree day following a freezing-cold night to spur on the running of the sap, and the maple sugaring season has started."

Deciduous trees pull their sap into the branches and trunk when the weather turns cold, so there is more sap to tap when the weather gets warm the next day. When I was growing up, we used to tap our trees in the late fall, and we would typically tap them both day and night. I suspect the other folks are right, though. Sap flows better in warmer weather, and it generally tends to be warmer in the day.

Answer 2

greater during the day due to the sun warming it up andd making it flow easyer

Answer 3

My first instinct would be to say daytime simply because the rise in temperature would lower the viscosity (make it thinner) of the syrup.

Just a guess though

Answer 4

The flow rate is greatest in the day due to transpiration and cellular respiration. In transpiration water is drawn up through a tree by evaporation from the leaves. This in turn pulls water up the xylem via capillary action. This water movement creates most of the pressure to drive sap flow. This is why sap flow is greatest at the warmest part of the day when most water is evaporating from the tree. Another factor is the fact that in spring the night temperatures can drop below freezing. This fluctuation in day to night temperatures helps drives the flow. After the night cools the sap contracts and draws water from the soil.

Cellular respiration also plays a role in generating internal pressure by releasing CO2 to the sap flow. The Cornell site explains the cellular respiration reactions and how they add to the transpiration pressure.

http://maple.dnr.cornell.edu/produc/sapf...

http://www.esf.edu/efb/course/EFB530/lec...

You are right in a way about the photosynthesis being a factor though. The sap is needed to provide the energy, via cellular respiration, to grow the new leaves the tree needs to begin photosynthesis for the new year. Sap flow begins before bud break to drive the growth process so the tree will have leaves to absorb solar energy, convert it to chemical energy, and store that energy over another winter for the next spring. Photosynthesis provides the energy then cellular respiration mobilizes the energy for growth.