The main objectives of this experiment were (1) to test the efficacy of two new platforms (a mounted platform and an over-the-row platform) on the time savings in labor for dormant pruning and fruit thinning, and (2) identify an optimal timing and method of sidewall shearing for apple. Trials were conducted in 2012 and 2013 at a Gala and Linda Mac Tall Spindle high density orchards on M.9 rootstock. Dormant pruning times using the platforms varied from 37% (using the mounted platform) to 47% (using the over-the-row platform) less time than with ladders. Hand thinning time using the over-the-row platform varied from 45% to 50% less time than with ladders for four people. These results with motorized pruning platforms indicated that a grower can achieve at least a 30-40% reduction in dormant pruning costs, or a 40% reduction in hand thinning costs with significant positive impacts on profitability.
Light exposure measurements showed that the summer sidewall shearing improved light intensity in the lower part of the canopy by about 25% and by about 10% in the mid-level of the canopy. There was little improvement of light exposure in the top of the canopy. The trees we used in these studies had canopies already quite well shaped for good light distribution and the shearing removed only a small portion of the shoots and thus had a small effect on light distribution in the canopy.
Our results with summer sidewall shearing were positive in 2012 and 2013 (little re-growth, relatively good return bloom) but will require 3 or more years to fully determine if this approach has long term positive results or if negative tree growth or yield reductions will negate the labor savings from mechanical sidewall shearing. In this study, the summer shearing treatments reduced yield for Gala by 18 to 28 percent in 2012 and up to 23 percent when compared to the control in 2013.
Labor cost and availability are major challenges to apple growing in the Northeast. Partial or full mechanization can significantly reduce labor costs and increase farm incomes. Its adoption can also improve the quality of life of Northeastern fruit growers. Platforms can be used for: dormant pruning, hand thinning, building trellis, leader selection, tree training, and summer pruning. The recent widespread adoption of the Tall Spindle apple system in the Northeast has provided continuing impetus to adoption of platforms.
We conducted on-farm research with cooperator Scott VanDeWalle who facilitated the use of two tractors with a mounted platform and an over-the-row platform. We also had the opportunity to use his hedger and a tractor every June, July, and August during 2012 and 2013 and initiated a long-term study of sidewall shearing with Gala and Linda Mac apple trees. We simultaneously conducted an extension program and had several educational activities during 2012 and 2013.
More than 200 growers that visited this site understood that mechanization is a way to keep up with the competition as labor costs rise and the supply of workers gets tighter every year. We hope to continue extending the benefits of orchard mechanization via the research conducted with the fruiting walls.
The objectives of this project were (1) to test the efficacy of two new platforms (mounted platform and over-the-row platform) on the time savings in labor for dormant pruning and fruit thinning, (2) initiate a sidewall shearing study to determine the pros and cons of this technology, and (3) use this site as a venue for educational activities and to generate field data for orchard mechanization publications.
2013 Winter Pruning Study with Two Type of Platforms: We conducted three timing studies to measure labor efficiency (with wet and snowy ground conditions) on March 4 and 5, 2013.
On March 4, we compared the pruning labor efficiency of two workers with ladders against the same two workers using a tractor mounted platform (a commercial platform designed by LaGasse Orchards, Lyons, NY). Start time and end time for pruning of tops of 12 Honeycrisp trees in one side and 13 Gala trees in the other side was measured first and then the time it took to complete the pruning for the bottoms. Then we timed the same two workers and pruned with ladders the tops and bottoms of adjacent and unpruned 12 Honeycrisp trees and 12 Gala trees. A third evaluation with the same two workers and same platform measured the start time and end time for pruning of tops and bottoms of 51 Honeycrisp trees and 53 Gala trees.
On March 5, we compared the labor efficiency of 4 workers with ladders against the same 4 workers using this time an over-the-row mounted platform (a prototype designed by LaGasse Orchards). Start time and end time for pruning of tops and bottoms of 220 Macoun trees was measured separately. Then we timed the same four workers and pruned with ladders the tops and bottoms of adjacent and unpruned 76 Macoun trees.
2013 Fruit Thinning Study with a Platform: The severe early spring frosts damaged the apple crop and we did not conduct the hand thinning timing trials with ladders or platforms planned for the 2012 season. On July 30 2013, we compared the hand thinning labor efficiency of four workers with ladders against the same 4 workers using the over-the-row mounted platform. Start time and end time for hand thinning of tops of mature 668 Gala and 1148 Honeycrisp trees was measured separately. Then we timed the same four workers and hand thinned with ladders the tops of adjacent 10 Gala and 10 Honeycrisp trees.
Shearing Studies: One study of side-wall shearing was initiated in the summer of 2012 using mature Gala and Linda Mac Tall Spindle apple trees on M.9 rootstock. Three side-wall shearing timings were compared (mid June, mid July, and mid August) and two severities in 2012 (16-18inches and 24-26inches from the trunk in each side of the tree row) and only one severity in 2013 (24-26inches from the trunk in each side of the tree row) compared to an un-sheared (untreated control). There were 4 replications of each treatment in both years. Immediately after the shearing treatments were applied, the number of shoots that were cut and the number of fruit that dropped were counted on the ground.
2013 and 2014 Return bloom and Shoot length (inches) Evaluations: The number of flower buds and the length of shoots developed below a cut were counted in each plot in May 14, 2013 and May 26, 2014.
2012 and 2013 Harvest Evaluations: The fruit produced by 10 Gala trees in each plot was counted and weighed in September 20, 2012. Linda Mac trees were not evaluated as fruit was lost in 2012. The fruit produced by a section of 3 Gala trees and 3 Linda Mac trees in each plot was counted and weighed in Sept. 24 2013.
Dormant Pruning with Two Platforms: Measurements of dormant pruning time using the platforms varied from 37 to 47 percent less time than with ladders (Tables 1 and 2). The best reduction in pruning time (47 percent) was achieved with the over-the-row platform that utilized 4 people in a Macoun Tall Spindle apple system. With the Tall Spindle system the speed, efficiency, and uniformity of pruning with both type of platforms was high compared with moving a ladder to each tree and climbing up to prune only one or two branches. The 47% labor pruning efficiency here reported with a new platform design is higher than we previously anticipated. On March 2009 we conducted a preliminary study(without snow on the ground), where we compared the labor efficiency of four workers with ladders against the same four workers using a self-propelled platform (N-Blosi 25), a self-propelled growerbuilt platform, and a tractor-pulled orchard platform atop a bin trailer. On average, the pruning time (minutes/tree) decreased from the standard treatment (with ladders) of 1.26 minutes/tree to 0.92 minutes/tree when the same workers utilized a platform to prune mature Gala and McIntosh’s tall spindle apple trees. The pruning platforms reduced labor costs by about 27-30 percent. There was little difference in labor efficiency between the types of platform used on 2009.
Hand Thinning with a Platform: Measurements of hand thinning time using the over-the-row platform varied from 45% to 50% less time than with ladders for four people (Table 3). The best reduction in hand thinning time (50%) was achieved with the Gala Tall Spindle apple trees. Again, the 45-50% labor hand thinning efficiency here reported with an over-the-row platform that can cover two full rows, with four workers is higher than previously reported. Measurements of hand thinning time using autonomous orchard vehicles compared with ladders for fruit thinning have varied from 25-35% in Pennsylvania studies to 36% in Washington studies.
# Cuts/tree and # Fruit/tree on the ground: The more severe sidewall shearing treatments in 2012 cut more shoots and dropped more fruit to the ground. Fruit counts on Linda Mac were minimal due to the minimal fruit set in 2012. The number of cuts was increased by 50-55 percent and up to 64 percent in August when compared to the less severe shearing treatment in 2012 (Table 4). When the sidewall shearing was done in June 2012 and 2013 we cut more shoots per tree than any other shearing timing. Fruit counts showed that the number of fruit cut off were similar for Gala and Linda Mac in 2013 (Table 5).
Return Bloom and Shoot Length: The sidewall shearing treatments applied in 2012 with a relatively low crop on Gala and a minimal crop on Linda Mac induced higher shoot growth for all treatments in 2012 than in 2013 (Tables 6 and 7). The length of the shoots produced was increased by 8 inches for Gala and 7 inches for Linda Mac when the June timing was compared during both summer seasons. The 2012 treatments produced more flower buds when the hedging was applied less severely in June, July, and August. The amount of flower buds produced was similar for all treatments. We measured a more substantial shoot growth with the June timing in 2013 and counted more floral buds as a result of hedging late in the summer of 2013. The highest number of flower buds for both cultivars was measured for the August treatment.
Harvest: Gala trees that were hedged closer to the trunk produced less fruit than the un-sheared Gala trees or the Gala trees that were hedged two feet from the trunk in 2012. Gala yield was reduced by 18 to 28 percent in 2012 and up to 23 percent when compared to the control in 2013 (Tables 8 and 9). The three timings for hedging, regardless of severity, produced less fruit than the un-sheared control. In 2013, all treatments produced less fruit than the un-sheared control and the biggest yield reduction was observed with the August treatment for both cultivars. Linda Mac yield was more reduced than Gala with the August treatment.
Our light measurements were conducted at the lower, middle, and upper part of the canopy for each cultivar in mid July in 2012. Light exposure measurements showed that the summer sidewall shearing improved light intensity in the lower part of the canopy by about 25% and by about 10% in the mid-level of the canopy. There was little improvement of light exposure in the top of the canopy. The trees we used in these studies had canopies already quite well shaped for good light distribution and the shearing removed only a small portion of the shoots and thus had a small effect on light distribution in the canopy.
Apple growers in NY are already beginning to implement platforms for winter pruning and at least 2 growers have begun using sidewall shearing.
Our results in 2012 and 2013 have been positive for the adoption of platforms to improve dormant pruning labor efficiency.
At least 30 growers have either purchased or built platforms in the last 3 years. Many others are trying to evaluate the economics of the purchase. The educational activities that we conducted at this site helped them determine the economic value of this technology.
Our results with summer sidewall shearing were positive in 2012 and 2013 but will require 3 or more years to fully determine if this approach has long term positive results or if negative tree growth or potential yield reduction will negate the labor savings from mechanical sidewall shearing.
We are encouraged so far in that there was little regrowth from the sidewall shearing treatments, but we measured a yield reduction for Gala and Linda Mac in 2013.
We plan to continue this experiment by repeating the same treatments on the same trees. A long-term strategy that a grower in France has implemented is to use annual side-wall shearing of Tall Spindle trees for 3 successive years with no other dormant pruning but in the third year to add a dormant winter corrective pruning to remove limbs that have become large and are causing internal canopy shading and poor quality.
Education & Outreach Activities and Participation Summary
Extension/Outreach Orchard Mechanization Articles:
Robinson, T.L., Hoying, S.A., Miranda Sazo, M., DeMarree, A.M., and L. Dominguez. 2013. A Vision for Apple Orchard Systems of the Future. New York Fruit Quarterly. Vol. 21:3.
Miranda Sazo, M. 2013. Work Smarter Not Harder. Editorial for New York Fruit Quarterly. Vol. 21:3.
Robinson, T.L. and M. Miranda Sazo. 2013. Advances in Mechanization of the Tall Spindle Orchard System: Part 2 – Harvest Mechanization Prospects. New York Fruit Quarterly. Vol. 21:3.
Miranda Sazo, M. and T. L. Robinson. 2013. Recent Advances of Mechanization for the Tall Spindle Orchard System in New York State – Part 1. New York Fruit Quarterly. Vol. 21:1.
Growers learned about this project and were shown platforms, hedgers, and videos of summer sidewall shearing during the 2012 LOF Summer Tour in July 24 (Stop 6 at the VanDeWalle site) (120 people attended).
Preliminary results of this project were presented by Dr. Robinson at the NY Expo in Syracuse in January 2013 (150 people attended).
We conducted a pruning workshop of mature Gala and McIntosh tall spindle trees, invited growers to prune on the platform, and see the fruiting wall we started in partnership with grower cooperator on February 18, 2013 (60 people attended).
The partial results of this project were also presented at the Geneva field day on August 1, 2013. Growers and employees had a hedger for them to see how Gala trees were hedged. (150 people attended)
We also published 2 orchard mechanization articles (attached) in the New York Fruit Quarterly in 2013. These results helped apple growers understand high density planting systems and the value of new technologies as platforms and hedgers and which one they should implement in the future (this publication reaches approximately 1,500 subscribers).
Preliminary results of this project were presented at the 2014 Winter Fruit Schools in Niagara and Wayne Counties in February 3 and 4 (talk titled “Our Vision of Orchards of the Future” by Dr. Robinson) (more than 100 people attended each time).
The grower cooperator for this project hosted again a pruning workshop as part of a Winter Pruning Tour in Wayne County on Thursday February 20, 2014. This meeting was free, did not require a pre-registration, and was open to all Northeastern fruit growers interested to improve orchard labor efficiency during the winter months. Approximately 60 growers from NY, 6 from North Carolina, 10 from Brazil attended the meeting.
We conducted an economic analysis of investment in a platform and utilized a relatively lower efficiency for pruning (30%) and for hand thinning (40%). We estimated that there are significant labor savings per acre when using orchard platforms versus ladders for several orchard jobs performed by hand labor. Economic comparisons in a tall spindle planting of 1,320 trees per acre showed that the use of orchard platforms could save $102/acre, $140/acre and $45/acre for dormant pruning, hand thinning and trellis wire installation, respectively (Table 10).
When long-term orchard profitability using Net Present Value of Accumulated Profit (NPV) was evaluated comparing a Tall Spindle system using orchard platforms versus ladders, orchard platforms increase profitability (Table 11). NPV was estimated to increase by $492/acre after 10 years and rise to $1127 after 20 years if platform use was a part of the management of a tall spindle orchard.
The examples shown in Tables 10 and 11 are for annual use of platforms for three jobs; trellis wire installation and tree tying, dormant pruning, and hand thinning. There are other jobs that orchard platforms can be used to perform such as summer pruning, fruit harvest, placing mating disruption dispensers in tree tops to name a few. There may be years where hand thinning is not necessary, but where the platform is used to perform other jobs.
The cost and time amounted to a fraction of the time (5%) to do manual summer pruning by utilizing a mechanical shearing machine. If side-wall shearing in the summer can reduce summer pruning costs by 95% and improve labor efficiency without negative effects on return bloom, vigorous growth response, or a significant yield reduction it will also have a significant impact on orchard profitability. Results from two seasons of summer shearing are encouraging so far in that there was little regrowth from the sidewall shearing treatments with the Tall Spindle system. We plan to continue this study we started in 2012 by repeating the same treatments on the same trees for the next 3 or more years.
A long-term strategy that on grower in France has implemented is to use annual side-wall shearing of Tall Spindle trees for 3 successive years with no other dormant pruning but in the third year to add a dormant winter corrective pruning to remove limbs that have become large and are causing internal canopy shading and poor fruit quality. Such a pruning strategy could reduce total annual pruning costs in Tall Spindle orchards by about 65% and help NY apple growers remain profitable and competitive.
There are at least 25 more growers who have either purchased or built platforms since this project was started with VanDeWalle.
There are at least 2 growers who have begun using sidewall shearing.
There is one manufacturer in Lyons, NY who recently sold a new hedger in March 21, 2014.
There are at least 5-7 more growers who are evaluating the economics of the purchase of a platform and then a hedger.
There is one grower who bought a machine for apple harvest from Washington.
There are two to three more growers who are exploring the possibility of purchasing a harvesting machine built in Washington and New York.
Areas needing additional study
We plan to continue this study we started in 2012 by repeating the same treatments on the same trees for the next 3 or more years. Our main goals are to measure any negative effects on return bloom, vigorous growth response, or any significant yield reduction for the most profitable apple cultivars in NY State.