Sugarbush Evaluation the Tubing System

Cornell Maple Camp 2012 Sugarbush Evaluation – The tubing system Five aspects of a sugarbush and maple tubing system will be evaluated. Tapping density, taps per lateral line, mainline sizing, vacuum sizing, and spout sanitation.

Items necessary per team: tree diameter tape, tape measure > 27’, vacuum gauge, Mainline guidelines, tools to measure slope, taps on mainlines counted prior to workshop?, vacuum on in the sections of woods to be used, recording sheets, spout samples.

Tapping Density Mark a center point in the sugarbush for a circle with a radius of 26'4'' Measure out the circle and count 1 tap for each tree 10" or more Alternative Measure out the circle and count 1 tap for each tree 10" to 20" diameter and 2 taps for each tree over 20" For each distinct section of sugarbush do this at least three times

Sugarbush section identification ______Site 1 Site 2 Site 3 Site 4 tap count x 20 Average

Input these averages into the cost spreadsheet for a cost per tap evaluation

Results: 1-20 taps per acre = difficult to operate commercially 21-40 taps per acre = low efficiency 41-80 taps per acre = medium efficiency 81-120 taps per acre = maximum efficiency 121+ taps per acre = over crowded, reduced sugar content of sap, slow growth

Explain: The more concentrated the taps in a woods the lower the cost per tap to install a tubing system. The negative of too many taps though could be lack of other species in the woods making it more vulnerable to insect and disease attack. Also overcrowding could lead to lower sugar content. Research from Canada has shown that with vacuum one tap for trees up to 20” is sufficient to extract available sap. Many producers will elect to put two taps in trees larger than 20” and there is no research data to indicate that this is not an acceptable practice. Taps per lateral line estimation Count the taps on each of 5 lateral lines in a sugarbush section and average

Sugarbush section identification ______

Lateral 1 Lateral 2 Lateral 3 Lateral 4 Lateral 5 Average tap count Average of the 3 sections _____

Results: 1-3 taps per lateral = tends to increase cost with very little sap yield benefit 4-8 taps per lateral = with average maintenance this seems to work best 9-12 taps per lateral = only should be used with top notch maintenance along with steep slopes 13-20 taps per lateral = generally results in reduced yields 21+ taps per lateral = generally results in reduced yields

Explain: Research done in Vermont has shown that reducing taps per lateral increases sap yield per tap. However, too few taps per lateral increases the installation cost per tap. The recommended ideal is 5 to 6 taps. More taps per lateral does reduce installation costs but also reduces production

Mainline size For slope, measure the slope of the flattest 20’ length of a mainline in its lower half

Use the slope determined above for the given mainline size to select the correct column to use on the tapping rate guideline sheet

Sugarbush section identification ______Mainline identification ______mainline diameter _____ mainline length _____ number of taps _____ number of taps from the guideline _____ # of taps more than guideline _____ # of taps less than guideline _____ Difference = # of taps more or less than guideline/guideline ______

Results: more than 25% below the guideline = good productivity but high installation costs Less than 25% below or above the guideline = Ideal for productivity vs. installation costs 25 to 35% more taps than the guideline = reduced productivity but lower installation costs More than 35% more than the guideline = lower cost low production system

Explain: The slope of a mainline determines how rapidly sap exits the mainline. However, if the slope of the line changes the flatter areas will bottleneck that flow, particularly lower in the line where the most sap is flowing in the line. Air flow needed to maintain vacuum in a mainline is restricted by sap flow. The guidelines for number of taps on a mainline take into account sap flow during an exceptional flow event and calculate how much capacity of the line must be free to remove the normal air leakage into the line to maintain excellent vacuum. Too many more taps and vacuum will be obstructed during good sap flow, too many less taps will be more expensive to install and can lead to sap warming as it moves through the system because of the lower flow rates.

Vacuum sizing Sugarbush section identification ______vacuum reading in inches at the pump _____ vacuum reading in inches near the bottom of the mainline _____ vacuum reading at the end of a lateral line near the top end of the mainline _____ Difference between the readings _____, _____, ____

Sugarbush section identification ______vacuum reading in inches at the pump _____ vacuum reading in inches near the bottom of the mainline _____ vacuum reading at the end of a lateral line near the top end of the mainline _____ Difference between the readings _____, _____, _____

Results: Difference within 2” of vacuum and above 15” = highest productivity and well designed tubing system Difference between 2” and 4” or vacuum less than 15” = lower productivity, tubing undersized or has slope change issues Difference greater than 4” or vacuum less than 10” = lower productivity and poor tubing system design No vacuum at the top = poor productivity, unacceptable system design

Explain: Research from various sources shows that sap flow increases with increased vacuum at the tap. Tubing systems that are undersized will obstruct the flow of leakage air through the mainlines and out to the vacuum pump in turn reducing sap yield. The larger the difference between the inches of vacuum early in the system vs. at the systems most distant points shows just how undersized the mainline system is. Most vacuum pumps are designed to perform well in the 12” to 18” range so we target having at least 15” available near the vacuum pump as a minimum.

Vacuum bonus points, cfm assignment suggested by the guideline = ______Estimated actual cfm available to the line = ______

Spout and tap sanitation evaluation Sugarbush section identification ______7/16" Health spout Check valve Silver Spout Tree saver Kind of spout ______Age of spout ______Age of drop ______

Sugarbush section identification ______7/16" Health spout Check valve Silver Spout Tree saver Kind of spout ______Age of spout ______Age of drop ______

Results: New check valve or new silver spout or new health spout and drop line = highest productivity 2nd to 3rd season old health spout and drop line or new tree saver spout = medium productivity 7/16 spout and old drop lines = poorest productivity

Explain: Research at Cornell and Vermont has shown dramatic improvements in sap yield can be obtained when some practice of preserving tap hole sanitation is used. The best results have been observed with new check valve spouts, new silver spouts, or new health spout with new drop line. Tree saver spouts or replacing the spout and drop every few years can be improving yield but less than those practices listed above. Systems still using the old 7/16 spouts and not updating drop lines in a systematic way will be creating more in tree partitioning and experiencing lower sap yield.