Commodity Adaptation

Nova Scotia’s Climate Adaptation Leadership Program (CALP) aims to support the province’s agricultural sector in developing and implementing climate change adaptation strategies to ensure long-term resiliency. The cattle and sheep, Christmas tree, and horticultural sectors have each developed their adaptation strategies and are currently implementing adaptation initiatives. Starting with these three commodities, the resources found on this page highlight practical advice on climate change adaptation considerations and practices.  

Cattle and Sheep

Horticulture

Christmas Tree

Soil

Cattle and Sheep

Drought Management on Pasture

Changes in precipitation patterns and increases in temperature mean we could see changes in summer growth patterns.

Key climate change impacts

Major impacts of drought include reduced forage yields and pasture regrowth which causes pasture managers to adapt.

Poor feed quality often results in poor body condition causing reduced fertility, reduced conception rates, decreased milk production, and suppressed immune system function.

Key Adaptation Strategy

Improving pasture health through soil fertility and grazing management

  • Drought lowers carbohydrates in the root system and weakens plants.
  • Don’t graze pastures too short- leave at least 10 cm of plant height. This promotes faster regrowth and helps preserve soil moisture
  • Strip, block and rotational grazing systems help

Reducing overall stocking rates

  • Remove bulls at appropriate time
  • Cull any cows that are not bred on time
  • Consider weaning calves early (or creep feeding)
  • Decreases pressure on pasture, and cows in advance of winter

 Sale of animals 

  • Sell calves earlier in the fall to decrease reliance on winter feeds
  • Cull cows more aggressively

Stockpile extra forage

  • This can be done by allowing a pasture to grow throughout the summer- may require feeding bales strategically in a sacrifice pasture during drier conditions.
  • Providing the rest during the dry part of the summer may allow you to continue grazing through the fall and early winter

Use drought tolerant plant species 

  • Ryegrass, orchardgrass, bromegrass have some drought tolerance
  • Bluegrass, timothy do poorly in drought conditions

Additional Resources

Extended Grazing

Rising temperatures due to climate change will lead to a growing shoulder season and shrinking, milder winters. While many risks are associated with these impacts, there are also benefits if adaptive management techniques are put in place.

In Atlantic Canada, overwintering livestock accounts for 60-80% of production costs, with a majority of that being due to stored forage needs. Extending the period in which livestock can graze is a way to reduce these costs with the added benefit of soil health and fertility improvements. To capitalize on this effectively, an extended grazing plan catered to your operation needs to be in place to maximize benefits and ensure pasture and livestock well-being.

Key Climate Benefit 

  • Later fall and earlier spring could lead to increased opportunities to extend the grazing season, leading to…
    • Reduced feed, yardage, and labour costs
    • Reduced reliance on stored feeds
    • Reduced need for hauling manure, bales, bedding
    • Improve soil health and fertility through manure

Options for extending the grazing season 

  • Controlled grazing
    • Rotational and strip grazing improve pasture productivity and longevity while also improving root presence to reduce mud and rut formation
  • Stockpile extra forage
    • Pasture (tall fescue, orchardgrass, alfalfa) left to grow without grazing from July onward enables grazing beyond late fall
  • Grazing annual crops
    • Annual ryegrass, brassicas (kale, rape, stubble turnips), standing corn, cereals (fall rye and oats) provide high quality feed later in fall or on regrowth in early spring
    • Note: nutrition issues can arise if corn and brassicas are sole food source – supplement with strip grazing, oat/rye mixes, and/or hay bales
  • Grazing cover crops
    • Cover crops on their own improve soil health and reduce runoff, when grazed they provide later season opportunities
  • Bale grazing
    • Bales placed on their side in the field provide feed when snow is deep or packed
    • In advance of winter, bales can be placed in a checkerboard pattern with temporary fencing controlling access throughout the season.
  • Early weaning
    • Early weaning conditions a cow before winter, improving their ability to graze in winter longer and reducing the need for supplemental feed

Note 

While we may see benefits like an extended grazing season, warmer shoulder season temperatures and increased precipitation will increase the risk of mud and field damage in soft, wet-prone areas due to a lack of frozen ground

  • When planning for extended grazing, choose an area that has:
    • Well-draining soil
    • Established sod or crops that can support livestock even in wet conditions
      • Rotationally grazed pasture helps with this
  • Only graze soft or poorly drained areas when soil is sufficiently frozen

Additional Resources

Heat Stress in Livestock

Changing climate conditions will lead to higher average temperatures, and more frequent extreme heat events and heat waves. Heat stress poses serious welfare and productivity issues for all livestock and will ultimately lead to lost revenue to farmers.

Heat stress awareness

Temperatures above 23C, combined with high humidity, stagnant air, and/or direct sunlight can lead to heat stress in cattle and sheep.

  • When THI reaches 72, moderate heat stress can occur, with very high humidity at temperatures of only 23C
  • At THI of 80, heat stress can become severe in animals which can happen at temperatures as low as 28C.
  • Heat stress in animals is more likely during sudden temperature increase, heat waves early in the year, or the early days of a heat wave.

Signs of heat stress

  • Reduced feed intake, increased water intake, change in feeding patterns
  • Animals only standing, congregating, over-crowding shade spots or water
  • Rapid shallow breathing, open-mouth breathing, panting
    • If >20% of cows exceed 100 breaths/minute –
  • Sweating, increased saliva, clumsy, and trembling
  • Sheep appear bloated

Key Climate Impacts

  • Reduced productivity: lower milk production, poorer milk composition, poor weight gain, and inefficient feed conversion
  • Reproductive issues: reduced semen quality and quantity, lower libido and lower birth rates
  • Immune system suppression: increased animal vulnerability to diseases and risk of lameness for prolonged periods following heat stress events

Key Adaptation Strategies

  • Shade: Plant trees, install shade cloths or permanent structures with full herd capacity
  • Water: Provide plenty of clean and cool water in localized, shaded areas
    • At least 1 station per 20 cows supplying 3-5 gal/min
    • Distance to water should be no more than 500 ft. (150m) for dairy cattle and no more than 1000 ft. (300m) for other livestock
  • Air flow: use fans, open indoor vents, limit time in pens
  • Other:
    • Rotationally grazed animals: rotate more quickly, in the evening, and select paddocks with tree access or other shade during high heat periods
    • Pasture-based dairy cows: use sprinklers during afternoon milking (check with Dan for relevance)
    • Sheep: shear in spring or early summer. If breeding out of season, shear rams 8 weeks in advance of breeding. Don’t shear during heat events.
    • Schedule activities (castrating, vaccinating, transportation) during cooler days or parts of the day
    • Use opaque calf hutches with adequate spacing allowing air flow
    • Mixing feed with an oil can increase feed intake during high heat events

References

Additional Resources

Find more resources on the Sheep Producers of Nova Scotia’s Climate Adaptation page here and the Nova Scotia Cattle Producer’s page here.

Horticulture

Biopesticides

Horticulture NS and industry stakeholders have identified increased pest pressures as a risk to the sector.

Key Climate Impact

Increasing temperatures and precipitation will likely result in a change in pest and disease distribution and the introduction of new pests. This may mean increased biopesticide applications, with all the higher costs associated.

Key Adaptation Strategy

With increased precipitation and the likelihood in the frequency and intensity of storms bringing significant rainfall over shorter periods, there is a need to ensure that biopesticide residues are maintained and not lost due to excessive precipitation. This may result in the need for increased applications.

  • Biopesticides should be used as part of an integrated pest management program.
  • Undertake regular scouting/crop monitoring.
    • Timing of application for several biopesticides is critical.
  • Ensure correct timings of application in relation to desired biopesticide for effectiveness.

Things to keep in mind when applying biopesticides:

  • Sulphur: Can cause phytotoxicty when temperatures are above 32o
  • Copper: Precipitation events or rapid plant growth may remove product residue reducing the protection period.
  • Trichoderma: Soil temperatures must be above 10°C for the Trichoderma to become active.
  • Fungicides Not Classified (Oils, Bicarbonates, Peroxides, etc.): Fungicide group has non-specific modes of action that work on contact, sensitive to weather conditions such as temperature, humidity, and rainfall.

Additional Resources

Frost Protection

Increasing temperatures – including earlier last spring frost and later first fall frost – could provide longer growing seasons and new opportunities for crops and varieties.

Unfortunately, while average springtime temperatures are rising and the growing season is lengthening, frost events can still occur within their historical time frame.  It is also likely to result in more variable temperature and weather patterns, meaning surprise frost events and the early and rapid development of crops within the historical frost window.

Key Climate Impact

  • Warmer spring temperatures cause crops to produce buds, blossoms, and vegetation earlier
  • Later springtime frost events can damage new growth
  • Frost events can devastate entire crops, reduce yields and produce quality, and cause damage to perennial or biennial crops that is carried into the future

Frost Types

  • Advective frosts are characterised by cold air moving into the region with strong winds. More intense and frequent storms are likely to increase the occurrence of these frosts.
  • Radiative frosts occur during clear cold, calm nights. These types of frosts tend to be easier to adapt to that advective frosts.

Key Adaptation Strategy:

Strategies for frost protection can be divided into 2 categories:

  1. Active methods
  2. Passive methods 

Active methods are used to protect plants during extreme weather events.

Passive methods tend to be more effective and economical but might limit adoption of new crops and varieties. Passive methods can help maintain a baseline of protection against frost, and tend to be more effective and economical, but can limit the adoption of new crops and varieties.

Passive Methods 

  • Site selection
    • Plant near trees and buildings – physically shelter plants from direct cold winds
    • Avoid overly stagnant areas – airflow reduces the settling of cold air
    • Plant on slopes – radiative cold air will pool in valleys
    • Plant near water – air over larger bodies of water tends to be warmer, cools more slowly
    • Plant in ideal soil types – avoid sandy soil which will lose water quickly and enable frost to form
  • Adapted crops and varieties: certain crops exhibit key growth stages outside of critical frost periods
  • Planting date: keep 5 to 10 year climate trends in mind when planning for future
  • Soil management: proper soil moisture, tillage, and mulch

Active Methods

  • Physical barriers: cover plants overnight to retain heat
  • Water barriers: use irrigation/sprinklers to continuously cover entire crop for cold temperature duration
  • Air movement: mix air via helicopter rotor wash, large ground-mounted fans, or propane fan-heaters to keep temperatures from dropping rapidly
  • Fog or smoke: expensive and challenging, but can be effective

Additional Resources

Increased Pests in Horticulture Crops 

The effects of climate change on plant parasite nematodes are unclear. However, you can take steps to begin preparing for any future negative impacts. 

Key Adaptation Strategies 

  • Follow an integrated pest management approach to maintain the nematode population density below economic thresholds.
  • Understand the different host stages of plant parasitic nematodes.
  • Practice select cover cropping. 
  • Use crop rotation and a selection of resistant varieties. 
  • Follow effective sampling protocols. 

Key Takeaways 

  • Different parasitic nematodes have different ranges. For example, root knot nematodes (e.g. Meloidogynes arenaria) have a wide range (500+), but some species have a restricted host range (e.g. M.partityla and M.ichinohei).
  • When considering the use of soil fumigants, their effectiveness can be greatly influenced by soil factors including texture, structure, organic matter, moisture content and temperature at the time of application. 
  • Consistent sampling protocols are helpful in determining nematode density and distribution patterns. 
  • Select cover crops that are non-hosts or are not susceptible to plant parasitic nematodes limiting opportunities for survival and reproduction. 

Additional Resources

Integrated Pest Management (IPM) 

Over the next 20 to 40 years, climate change is projected to result in more variable precipitation and temperature patterns, along with more frequent and intense storms.

These changes will increase pest pressures due to shifting distributions, altered lifecycles, reduced overwinter mortality, and heightened crop vulnerability from damage and stress caused by adverse weather events.

Key Climate Impact

Rising pest pressures and weakened plants will demand more frequent and novel sprays, resulting in negative impacts to:

  • Production costs
  • Environmental and health concerns
  • Consumer food safety perceptions

Insect and disease monitoring: 

Suitable pest monitoring practices ensures plant protection products like insecticides and fungicides are only implemented at the most effective time to reduce spray frequency, reduce costs, and protect the environment.

Insect and disease monitoring is an essential step in integrated pest management (IPM).

  1. Knowledge – informed on crop characteristics, associated potential pests, and control options
  2. Record keeping – maintained cropping, management, and species history specific to each field
  3. Adaptability – openness to changing site management, application timing, and safety and control techniques
  4. Monitoring – tracking of weeds, disease, and insect distribution, and crop health via scouting and sampling
  5. Action thresholds – determined level when pesticides should be implemented at times that maximize benefit and limit financial costs and losses

Key Adaptation Strategy

Use Perennia’s Online Pest Management Guide

  • Regularly inspect crops for pests and/or pest damage
    • E.g. Count the number of insects on one leaf
  • Regularly inspect traps
    • E.g. Count the number of insects on a trap by insect type
  • Identify the pests that are present and be informed on characteristics like life cycle, habits, natural predators
  • Determine growth stage of pest – most effective treatment will be time-dependent
  • Monitor weather conditions favourable for pest development with the use of Weather Stations

References 

Find more resources on Horticulture Nova Scotia’s Climate Adaptation page here.

Christmas Tree

Remote Sensing

Christmas tree production represents a significant contribution to Nova Scotia with production ranging from one end of the province to the other. Typically, N.S. experiences cold falls and relatively low summer temperatures which create a higher quality product.

Warmer falls, more rainfall and milder winters can increase pressures on needle retention, insect cycles and overall tree lot management.

Remote sensing provides data to decision makers on the farm. Typically, the data is much higher resolution and timelier that what is generally available. Currently the most readily available option is to use a drone fitted with regular and/or multi-spectral cameras to survey the lot. Drones can map anywhere from 50-500 acres/hour depending on the settings, though higher resolution requires more time.

Once complete, the dataset can help people determine tree densities, road networks, elevation changes, ground cover, areas of weed pressure, generate spray prescription maps, and in the future will help identify disease pressures.

Key climate Change Impacts

As the province experiences more rainfall and high precipitation events it will be important to understand tree lot topography to better layout drainage ditches, roads and culverts.

Milder winters may lead to increased insect pressures which can damage tree health so being able to survey entire lots and use software to identify issues will save labour. It shouldn’t be assumed that this will replace visual inspections though.

Spray programs are also an integral component of some tree lot management. Spraying by backpack sprayer can be costly and time consuming so having a better idea of where weed pressures are can create efficiencies.

Key Adaptation Strategy

Using real time and landscape level data to make more informed decisions about tree lot infrastructure and spatial management.

Resources

Warmer Temperatures and Needle Retention

Changing climate conditions will lead to milder winters, a longer frost-free season, higher daytime and nighttime temperatures, and longer, more frequent heat waves.

Key Climate Change Impacts

Historically, cold fall weather leading into winter triggered a physiological response in fir trees that allowed for greater needle retention. As the fall season lasts longer and becomes warmer due to climate change, this response is becoming delayed, leading to an increased risk in harvesting trees before cold acclimation and poor needle retention.

Key Adaptation Strategies

Preharvest 

  • Use genotypes with high needle abscission resistance (NAR) which allows the physiological response to occur at warmer temperatures.
  • Avoid over-fertilization. Excessive nutrition decreases needle retention.
  • Assess trees for high needle retention, often indicated by more flexible needles and slightly less needle density along branches.

Harvest

  • Monitor weather stations and harvest based on ideal temperature and not time of year.
  • Wait as late into the season as possible to begin harvest, ideally after a few frost events.

Post-harvest storage

  • Keep trees in temperature-controlled cold storage
  • Use white or blue LED lights instead of complete darkness
  • Maintain a low vapor pressure deficit (e.g. cool temperature, high humidity, sheltered from wind)
  • Use an ethylene inhibitor to delay needle loss

Shipping 

  • Protect trees from direct sun or wind exposure
  • Transport in a clean, acclimatized environment (generally, 1°C; 45 min before arriving at the retailer, increase to 4°C)
  • Keep container doors closed with maintained humidity

Retailer

  • Keep trees in container and only move to display when sales demand is high
  • Maintain display areas to be covered and cool
  • Give trees a freshly cut when moving them to display and put them in water
  • Replace stands with new fresh water frequently
  • Give trees a fresh cut again once they are sold

References

  • Lada, R. R., & MacDonald, M. T. (2015). Understanding the physiology of postharvest needle abscission in balsam fir. Frontiers in plant science, 6, 1069.
  • MacDonald, M. T., Lada, R. R., MacDonald, G. E., Caldwell, C. D., & Udenigwe, C. C. (2023). Changes in Polar Lipid Composition in Balsam Fir during Seasonal Cold Acclimation and Relationship to Needle Abscission. International Journal of Molecular Sciences, 24(21), 15702.

Insects – Balsam Woolly Adelgid  

Warmer temperatures, increased rainfall, and more intense storms are creating conditions that favor pest survival and reproduction. Nova Scotia Christmas tree growers are already familiar with balsam woolly adelgid (BWA, Adelges piceae), a pest that exclusively targets true firs. While BWA is not new to the industry, its impacts are expected to increase in a changing climate. 

Managing for BWA is essential because this pest can cause severe damage to balsam fir (Abies balsamea) Christmas trees. Effective management can prevent tree mortality, maintain tree quality, and ensure the sustainability of the Christmas tree industry in Nova Scotia.

Key Climate Change Impacts

  • Temperature Increases: Warmer temperatures enhance the survival and reproduction rates of BWA, leading to more severe infestations. Sites with seasonally warmer temperatures tend to demonstrate higher degrees of insect-induced forest degradation. 
  • Precipitation Changes: Increased rainfall can create favorable conditions for BWA and other pests, while hotter temperatures may cause drought stress for trees, making them more susceptible to infestations. The combination of warm temperatures and adequate moisture can accelerate the growth and spread of BWA populations. 
  • Extreme Weather: Stronger storms and wind can damage trees, making them more vulnerable to pest attacks.

Key Adaptation Strategies

  • Integrated Pest Management (IPM): Regular monitoring 
    • BWA can be identified by the presence of tiny (1-2 mm) white cottony tufts on the bole or branches of infested trees. These tufts conceal amber-colored eggs and stationary feeding adults, which are dark purple and nearly round. 
    • Look for signs of pests at branch nodes and buds (twig attacks), or on the main stem of the tree in extreme cases (stem attacks) 
    • Twig attacks will result in swelling at nodes and buds, and stunted growth leading to fiddle-shaped crowns 
    • Stem attacks will result in foliage of trees turning yellow and then deep red/brown 
  • Integrated Pest Management (IPM): Biological controls and judicious use of chemical treatments can help manage BWA populations. 
  • Forest Management: Thinning tree stands to improve airflow and reduce moisture, and diversifying tree species can reduce the risk of widespread pest outbreaks. Removal of overmature and susceptible balsam fir will also aid in reducing outbreaks of BWA. 
  • Climate-Resilient Practices: Planting resilient tree species and varieties, maintaining healthy soil, and proper irrigation can improve tree health and resistance to pests. 

Resources 

Find more resources on the Christmas Tree Council of Nova Scotia’s Climate Adaptation page here.

Soil

Benefits of Soil Organic Matter

Soil organic matter (SOM) is vital for soil processes essential to plant growth. Nova Scotia soils are (generally) naturally low in soil organic matter, and intensive crop production can further deplete it.

Depleted soils combined with climate change (including rising temperatures, increased precipitation, and more frequent extreme weather) leaves agricultural soil in Nova Scotia vulnerable to drought, flooding, erosion, nutrient loss, and reduced productivity.

SOM helps to

  • Provide and retain nutrients
    • Reduced fertilizer cost
    • Enhance nutrient cycling
    • Protected ground and surface water
  • Strengthen soil structure and increase aggregate stability
    • Reduced soil erosion
    • Maintained soil pores for water and air movement
  • Increase soil water-holding capacity
    • Reduced flood risks
    • Increased soil resiliency during drought
    • Maintained productivity/plant-growth during wet and dry periods

Adaptive practices: Use of BMPs to preserve existing SOM and add more.

  • Adding raw plant material like mulches, plant residue, chop-and-drop cover crops will physically protect soil and provide nutrients and carbon when broken down.
  • Adding manure can provide a significant amount of nitrogen and other nutrients – injection or incorporation reduces atmospheric losses, i.e. nitrogen gas.

Note: plant, food and/or animal waste material that is properly composted can be more stable in soil resulting in reduced:

  • Atmospheric nitrogen and carbon loss
  • Harmful pathogen over-exposure
  • Weed seed presence

Additional Resources

General Soil Management for a Changing Climate

Soil is the foundation of agriculture in Nova Scotia and a changing climate is putting it increasingly at risk. More frequent and intense storms and heavy rainfall will affect soil erosion, field accessibility, and drainage requirements, while rising temperatures will affect germination timing, planting dates, and plant health and water availability. These impacts will require farmers to adapt their management practices to protect their soil and the crops it supports.

Proper soil management can improve nutrient use efficiency, reduce drought stress, enhance water efficiency, prevent erosion, and improve plant heath. Soils are influenced by three key properties: chemical, biological, and physical. Maximize benefits to these areas by improving overall nutrient management and implementing practices which build soil health.

Adaptive practices to build soil health:  

  • Add organic material like compost, composted manure or chop-and-drop cover crops to:
    • Supply organic matter (OM), food for microorganisms, nutrients
    • Improve nutrient transfer between soils and plant roots
    • Provide building materials for soil aggregates
    • Improve water holding capacity (OM acts like a sponge)
  • Use cover crops to:
    • Protect soil from erosion and nutrient lost
    • Protect soil microorganisms
    • Provide OM, energy, and nutrient supply
    • Provide nitrogen if using nitrogen fixing cover crops
    • Maintain root structures which provide water, gas and nutrient pathways, and microorganism habitat
  • Reduce tillage and decrease soil physical disturbances to:
    • Maintain soil structure, leading to reduced erosion, improved soil porosity, and microorganism habitat provision
    • Reduce rapid decomposition and nutrient loss to atmosphere and/or groundwater
  • Diversify crop rotations to:
    • Provide variety and wide range of energy and nutrients
    • Break up pest cycles
    • Provide diverse root system to help with aeration and water movement
  • Implement tile drainage to:
    • Improve whole-field slow draining soils or target wet-prone areas
    • Enable earlier field access
  • Add lime to:
    • Maintain consistent soil pH
    • Improve nutrient use efficiency and plant availability

Additional Resources