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Technical
Lawn Speeds and their Measurement

by Louis Nel

Lawn speed is an important consideration for enjoyable croquet. When comparing lawn A to lawn B as regards speed, we call lawn A faster than lawn B if, for the same initial velocity, a croquet ball will roll further on lawn A than on lawn B.

For two weeks before the World Croquet Championship of 1998 (in London, UK) the lawns were not watered so that they could be faster. It did not rain for another week after the start. In that kind of situation, the desire of the greenskeeper may well become in conflict with the desire of the players.

There are two reasons why faster lawns (up to a reasonable limit) are generally considered preferable to slower lawns. On the faster lawn, full rolls and pass rolls can be executed with control over longer distances than on slower lawns. In fact, on a really slow lawn, the routine split shot to hoops 2 and 3 after scoring hoop 1 can sometimes not be executed at all. Some standard rush shots are likewise impossible. This is frustrating to the player who has spent a lot of time practicing these basic shots only to find (at a certain tournament) that he cannot put them to use and must now resort to a more primitive style of play.  A second reason, is that for play near the hoops a  faster lawn better separates the men from the boys - a slow lawn is too forgiving of slipshod play. 

In view of the above, it is useful to have an objective measurement of lawn speed, suitable for  comparison of lawns at different  venues. Such a measurement already exists: the well known Time Test. To apply it, one measures the time (in seconds) that a ball takes to come to rest on the North boundary of a full court after being struck on the South boundary.  However, it is relatively cumbersome to apply this test. Two people are needed, one to strike the ball, the second to measure the time. Most of the time the struck ball - being the uncooperative inanimate object which it is - will not come to rest exactly on the north boundary, but be a few feet too long or  short.  So a lot of trial shots need to be recorded, with tabulation of the erroneous distances reached and corresponding times measured, and interpolation and averaging applied before an accurate measurement is possible. 

This calls for simplification. So we invented the Standard Ramp Test (SR test) for lawn speed. It can be done by one person in just a few minutes, with simple equipment which is easily transportable and widely available. (Those familiar with the Stimpmeter tests used for Golf greens, will notice some similarity while recognizing that the Standard Ramp Test introduced here is more precise and more suitable for comparison of lawn speeds at different places measured by different people. For theoretical discussion of rolling croquet balls and further discussion of distance based mesurements, see the article of Ian Plummer elsewhere on this website).

Equipment needed.

(a)    An ordinary straight rectangular plank about 6 inches wide and ¾ inch thick  and of length at least 48 inches, preferably an inch or so longer. If it is longer than 48 inches, then a distance of  48 inches from its end should be clearly marked by a line across on the upper surface  and a similar line on its lower surface directly below the one on the upper surface.

(b)   a measuring tape capable of measuring up to about 16 feet (for most lawns; for an exceptionally fast lawns a longer tape is useful).

Procedure for applying the Standard Ramp Test

ramp test

Step 1.

Install the plank so that the  48" mark on its bottom side is at rest exactly 12 inches above the ground while its opposite end rests on the ground. A convenient way of doing this is to let that 48" mark on its bottom surface lean on the crown of a hoop. A hoop should (by croquet rules/laws) be installed so that the top of its crown is exactly 12 inches above the ground. On a given hoop this may be a little off, so for an accurate application of the SR test, check the height of the crown and correct if necessary before proceeding.(No skidding was noticed in our tests, of either ball on ramp or ball on grass)

Step 2.

Place a croquet ball so that it rests on the 48" mark on the top surface of  the plank, equidistant from the two sides.  Let go of the ball without pushing it and let it roll down the ramp onto the lawn until it naturally comes to rest. Care should be taken to ensure that the ball does not run off the plank before reaching the bottom.

Step 3.

Measure the distance the balled rolled on the lawn i.e. the distance from the lower edge of the plank to the center of the ball in its rest position.

For a good measurement, Step 3 should be repeated several times and the average taken. That average is the Test Distance obtained i.e. the looked for Test Result.

The distances of successive balls traveling over the same terrain will normally differ very little, typically by no more than 6" over a distance of 14 feet.

If  there is any reason to believe that the terrain used is not typical of the whole lawn, then the whole test should be repeated at various places and the various Test Distances obtained should all be recorded and reported. This is particularly relevant where there is a discernable slope in the lawn. The recorded measurements should state, for example, that the North to South Test Distance is 14'6" while the South to North distance is 13'6".

Step 4.

The following should be recorded.

  1. Place of measurement (Club, Lawn)
  2. Date and Time of measurement
  3. Remarks (to elaborate on any relevant special circumstances)
  4. Name of person who did the measurement.
  5. Test Distance(s) measured.

Since lawn speeds vary considerably over the course of the season (generally slower in spring than in midsummer), and with wetness of the soil, length to which grass has been cut, the Remarks in (c) can be very important so as to convey an accurate impression. The absence of remarks will suggest that there was nothing special as regards wetness or cut to report i.e. that it seemed a typical speed for the time of year suggested by the date and time of day.

Wait, if possible, until all dew has evaporated.

List of  recorded Standard Ramp Test esults

 

a) Place b) Time c) Remarks d) Measured by e) Test distances Timed
(sec)

National Croquet Center, West Palm Beach, FL

a typical one of their 12 courts

21/02/05 at 12:00 noon.

Dry soil and grass well cut

Louis Nel and Ken Shipley

from Hoop 1:
Northbound 14'5"
Southbound 14'11"

12

Carleton U Fieldhouse (Ottawa)

typical of large carpeted area

18/02/05 at midmorning (time irrelevant here)

Carpeted surface not variable except for slope

Louis Nel and Ken Shipley

Northbound 22'
Southbound 21'5"

14
(both directions)

North Toronto LB and Croquet Club

typical area

08/05/05, around noon

Sunny, but with spring dampness, well cut

Louis Nel

13'11"

 

Puget Sound Croquet Club

typical area

04/06/05, around 6 p.m.

Freshly cut

Louis Nel

14'0"

 

Surbiton CroquetClub, London, UK

Lawn 2, typical area

21/06/05, Morning

Freshly cut at 6mm, Dawson Balls, 25'C

George Noble

14'0"

12

Hurlingham CroquetClub, London, UK

Front lawn

2/07/05 Noon

short, just prior to Open, Dawson Balls

Samir Patel

 

10

Your measurements...

           

We invite players to do an SR measurement at their club and send it to us for posting. We would like to collect this information from as many venues as possible: Louis Nel can be contacted on acna (at) magma.ca

19 May 2005

Author: Louis Nel
All rights reserved © 2005


Updated 28.i.16
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