Stone Fruit: Are You Stressed?

Stone Fruit: Are You Stressed?

When you drive through the orchard and see trees that are performing poorly or dying, it can be a source of tremendous stress to you as a grower. For the trees you just observed, they too, may be experiencing significant stress!

Plant stress is driven by numerous factors that adversely affect plant health, growth, productivity, and survival. Some stress factors directly impact tree assimilate dynamics (acquisition and utilization of water, nutrients, energy, and carbohydrates — see figure). These factors are living (biotic) or non-living (abiotic). Often, multiple stress factors can occur simultaneously or successively. Some stresses are chronic (systemic viral infection) while others may be acute (temporary drought).

Avoiding Stress

The first key to managing orchard stress is to avoid it in the first place through good management. Indeed, many stressful orchard conditions can be avoided if you choose a good site, pre-plant fumigate the soil, and choose the proper rootstock. Further, choosing the correct cultivar based on chill hours for your region and pest/disease tolerance is vital. Planting trees at the proper soil depth (graft union 4 inches above soil line) is necessary to keep feeder roots in the proper soil zone and to enhance tree stability.

Careful use of orchard machinery and proper timing and use of pruning tools can minimize damage to tree trunks and promote rapid healing of wounds on scaffold branches and limbs, respectively. Proper crop load management through pruning and thinning can facilitate strong scaffolds that won’t break under the pressure of a heavy crop. Finally, careful weed, pest, and disease management combined with adequate water and fertility can help to keep trees productive and healthy.

When speaking about orchard stress, it is also important to make several distinctions. It may be localized (part of a single tree or a few trees near each other) or it may be widespread (hundreds of trees in a low spot where there was standing water). One type of stress can exacerbate another — for example, trees that have been hit by hail causing numerous bark and trunk wounds provide attractive sites for lesser peach tree borer females to lay eggs or disease entry.

Some types of stress are reversible (i.e., nitrogen deficiency) while others (systemic viral infection) will persist throughout the life of the tree. It is also important to consider the timing of stress relative to key phenological growth stages. For fruit during the period of final swell (last two weeks before harvest), drought stress could have a very significant adverse impact on final fruit size. In severe cases of heat/drought stress, trees may actually drop fruit prematurely.

Identifying Stress

A key to managing orchard stress is being able to identify what is occurring with the goal of rectifying the situation or managing it to the greatest extent possible. There are numerous biotic stresses that adversely impact peach trees. These include insects, fungal diseases, bacterial diseases, viruses, viroids, mycoplasmas, nematodes, weeds, and even browsing animals (i.e., deer). There are numerous abiotic stresses, as well. These include solar radiation (sunburn), air and soil temperature (too hot or cold), inadequate chilling, rainfall (too much or too little), soil pH (too high or low; 6-7 usually best), soil nutrition (deficiency or excess), soil structure and aeration, excess wind, hail, herbicide drift, and even air pollution (ozone, sulfur dioxide, and hydrogen fluoride).

Finally, it is of vital importance to deal with factors that you can control and to consider the long-term impact on the tree. For example, if a block is compromised by hail, abandoning it until next year without a minimal fungicide/insecticide program to protect the tree and help minimize wound infection or boring of insects would be unwise. Some modest efforts could help to facilitate healing and significant recovery for cropping next year. Keeping good records from one year to the next by block will help to remind you of trees that had problems, what corrective measures were taken, and what the response was. Lastly, try to learn from and not repeat errors. We all make them but the wise person learns from them and doesn’t repeat them.

Leave a Reply

Featured Stories

All Vegetables Stories >All Fruits Stories >All Nuts Stories >All Citrus Stories >

The Latest

Apples & PearsBig Apple Crop Expected
September 2, 2014
Generally high quality predicted at U.S. Apple Association Crop Outlook and Marketing Conference. Read More
Apples & PearsBeware Of Fruit Rots During Apple Harvest
September 2, 2014
Conditions lately have been ripe for fungi fiasco. Read More
Apples & PearsThey’re Back! 2014 Brown Marmorated Stink Bug Populat…
September 2, 2014
Pressure building as traps filling up with pest by the hundreds. Read More
Farm ManagementStudy Shows ‘Megadrought’ On The Radar For …
September 2, 2014
Global warming trends fuel parched prediction from scientists. Read More
Farm ManagementTrimble’s Connected Farm Now Includes Field Data Mana…
September 2, 2014
Trimble adds two apps that work with their Connected Farm Web-based solution, providing growers and their advisors with more detailed field information. Read More
FruitsTips To Help You Manage Postharvest Ripening
September 2, 2014
Humidity, ethylene, and temperature can all impact fruit quality. Read More
CitrusHarness The Marketing Power Of Video
September 1, 2014
Multimedia platform is an effective and inexpensive marketing tool for you to attract new customers and keep existing ones loyal to your brand. Read More
Citrus Achievement AwardDespite Industry Challenges, Florida Citrus Leader Has …
September 1, 2014
2014 Florida Grower Citrus Achievement Award winner Mike Sparks feels confident in crop sector's ability to regain strength. Read More
Florida Ag ExpoFood Safety Modernization Act Is On The Plate
September 1, 2014
Florida Ag Expo agenda to serve up important features of looming regulations. Read More
CEU SeriesCEU Series: Put Weeds Out To Pasture
September 1, 2014
No matter where they are, plants out of place can be problematic. Read More
TomatoesProduction Reaches An All-Time High For Processing Toma…
August 29, 2014
A record high is predicted for the 2014 processing tomato crop. Read More
CitrusFlorida Department Of Citrus Knocks NPR Piece Over Juic…
August 28, 2014
Agency goes to bat for the industry regarding statement slighting OJ's health benefits. Read More
Disease ControlLate Blight Update Reveals Heightened Activity
August 28, 2014
While several states in the Northeast have confirmed the presence of late blight, the disease has not been reported in North Dakota or Minnesota. Read More
CitrusFlorida Energy Firm Charged Up About Citrus Biomass Pot…
August 28, 2014
Machine called a game-changer when it comes to a cost-effective, efficient way for tree removal and re-purposing. Read More
EquipmentNew Tractors Improve Maneuverability And Operator Contr…
August 28, 2014
The Magnum Rowtrac tractors from Case IH meet growers’ cropping needs through a wide variety of row spacing and belt options.   Read More
NutsCalifornia County Passes Ordinance To Protect Walnut Gr…
August 27, 2014
Verification of ownership needed to complete sales of valuable nuts. Read More
NutsAlmond Growers Hit By Russian Import Limits
August 27, 2014
Growers reflect on changes to export market in light of produce ban. Read More
Farm ManagementLeadership And Management Expert To Speak At California…
August 27, 2014
Daniel Goleman will make presentation at California State University-Fresno. Read More