S4ag Climate Adaptation

---
name: s4ag-climate-adaptation
description: "Help with climate vulnerability on the farm: drought planning, flood risk, heat stress, shifting frost dates, variety selection, and building biological resilience against extreme weather."
allowed-tools: [Read]
---

# Climate Adaptation

Your farm's exposure to climate change is specific — your soil type, elevation, enterprise mix, and water situation determine which risks are real and which are noise. This skill helps you identify the vulnerabilities that actually matter for your operation, then builds a prioritised response that starts with the cheapest and most durable adaptation available: healthy soil biology. Infrastructure comes after biology; biology comes first because it is almost always cheaper, faster, and more lasting than capital works.

**How this skill works:** Each sub-tool pauses at a **Checkpoint** to confirm the assumptions it is about to build on before producing output. A recommendation built on a wrong assumption wastes time and money — confirm the checkpoint before acting. Each sub-tool ends with **Next steps** — the skills worth running once you have acted on this one.

---

## Expert Lineage

*The thinkers whose frameworks underpin this skill — and what they specifically discovered that changes how you farm.*

**Charles Massy — Five Landscape Functions as Resilience Metrics**
Massy's framework from *Call of the Reed Warbler* identifies five landscape functions that determine how a farm responds to climate stress: solar energy conversion (photosynthesis), water cycle (infiltration vs. runoff), mineral cycle (nutrient availability), biological community dynamics (diversity of organisms), and human-social context. His specific finding: farms that score well on all five functions withstand drought, flood, and heat events that devastate neighbouring operations with similar rainfall and soil type. Function-based management is more climate-resilient than input-based management. The practical implication: assess your five functions before investing in infrastructure — the functions tell you where the farm is most exposed.

**Wes Jackson — Perennial Polycultures as the Climate-Resilient Agricultural Model**
Jackson at the Land Institute spent decades making the case, backed by agronomy, that annual monocultures are structurally fragile in the face of climate variability. Perennial polycultures — diverse, deep-rooted, self-maintaining systems — buffer temperature and moisture extremes that annuals cannot survive. His specific contribution: documented that the deep root systems of perennial grasses access water and nutrients beyond the reach of annual crops, dramatically extending the effective drought window before yield loss begins. On a conventional annual farm, the transition pathway starts with introducing perennial elements, not abandoning annuals.

**Gary Paul Nabhan — Place-Adapted Varieties and Arid-Land Resilience**
Nabhan's ethnobotanical research in the Southwest documented crop varieties adapted to extreme heat and irregular rainfall — varieties that conventional breeding abandoned in favour of high-yield performance under irrigated, ideal conditions. His finding: locally adapted landraces have survival mechanisms — stomatal regulation, root architecture, osmotic adjustment — that commercial varieties lack, and these mechanisms persist through epigenetic inheritance in seed populations adapted to a place over generations. The practical implication: sourcing varieties from your climate analogue region (the climate your region will become) delivers more resilience than any single variety bred for current normals.

**Elaine Ingham — Biology as Drought and Flood Insurance**
Ingham's soil food web research establishes the mechanism by which healthy biology buffers climate extremes. High-OM soils hold up to 20 times their weight in water — the difference between a 15mm rain event that runs off a 1% OM soil and infiltrates on a 5% OM soil. Fungal hyphae physically bind soil aggregates, keeping structure open for infiltration; the same aggregates reduce erosion during flood events. Her specific finding for climate adaptation: the fungi-to-bacteria ratio predicts soil water behaviour — fungal-dominated soils with stable aggregates infiltrate and retain more water than bacterial-dominated, compacted soils. Before spending on irrigation infrastructure, ask what the biology is doing.

**IPCC Working Group II — Agricultural Adaptation Evidence Base**
The IPCC WGII agricultural adaptation chapters document what is actually happening to farming systems under climate change by region: growing season shifts, heat stress thresholds for key crops, changed pest and disease pressure, altered water availability. Their specific contribution: region-specific risk mapping that moves adaptation from abstract concern to identifiable, bounded vulnerabilities. The practical implication: each farm sits in a regional risk profile — temperature trend, precipitation trend, extreme event frequency — and that profile sets the priority order for adaptation investment.

**David Montgomery — OM as the Cheapest Climate Adaptation Available**
Montgomery's work in *Growing a Revolution* documents farms rebuilding organic matter in years, not decades, when management shifts comprehensively. His specific finding: a 1% increase in soil OM at 30cm depth across a hectare holds approximately 160,000 litres of additional water — equivalent to 160mm of rainfall. The cost of building that OM through cover crops, compost, and reduced tillage is a fraction of the cost of equivalent irrigation infrastructure. Climate adaptation framing for conventional farmers: OM building is the best return on investment available.

---

## Which tool fits

| You need to... | Tool |
|---|---|
| Identify which climate risks are most acute on your farm | risk-assessment |
| Plan for drought or manage flood exposure | water-resilience |
| Reduce risk through variety and enterprise mix | diversity-as-resilience |
| Buffer climate extremes with physical infrastructure | infrastructure-adaptation |
| Choose varieties suited to a warming or drying climate | variety-selection |

## Routing Decision

- **Unsure where to start — general climate concern** → risk-assessment (always the first step)
- **Drought has hit or is coming — need water-holding strategies now** → water-resilience
- **Losing crops or income when a single enterprise fails in bad years** → diversity-as-resilience
- **Considering polytunnels, windbreaks, shade, or other physical adaptation** → infrastructure-adaptation
- **Looking for heat-tolerant, drought-adapted, or frost-shifted varieties** → variety-selection
- **Have the risk map, now want an integrated response** → run all sub-tools in order

---

## Risk Assessment

*Maps the farm's specific climate vulnerabilities by enterprise type and produces a prioritised action list.*

Climate risk is not generic. A grain farmer on light sandy soil in a drying region faces a different profile from a dairy farmer on heavy clay in a flood-prone valley. The starting point is always the specific farm in its specific place.

**Step 1: Identify the farm's climate trend.**

Work through these questions:

- What has changed in the last 10–20 years that the farmer has noticed? (Later frosts, earlier dry spells, more intense rain events, higher summer temperatures)
- What do regional climate projections say about temperature trend, precipitation trend, and extreme event frequency for this location? (IPCC WGII regional chapters, national meteorological service projections)
- What are neighbouring farmers or local land managers reporting?

**Step 2: Map enterprise exposure to each risk type.**

| Climate risk | High-exposure enterprises | Lower-exposure enterprises |
|---|---|---|
| Drought / reduced rainfall | Annual crops, shallow-rooted vegetables, irrigated systems | Deep-rooted perennials, native pasture, agroforestry |
| Heat stress | Brassicas, leafy crops, cool-season annuals, dairy cows | Heat-adapted varieties, dry-land grain, managed woodland |
| Flood / waterlogging | Root vegetables, annuals on clay soils, low-lying enterprises | Perennials on high ground, reed bed systems, water-tolerant species |
| Shifting frost dates | Orchards (frost at blossom), early-season vegetable growers | Late-sown annuals, frost-tolerant varieties |
| Increased pest/disease pressure | Monocultures, high-humidity crops, stressed crops | Diverse rotations, biologically healthy systems |
| Extreme weather events | Crops in ground during events, infrastructure on exposed sites | Tunnel crops, stored product, diversified systems |

**Step 3: Assess the biological foundation.**

Before evaluating any adaptation option, assess the farm's biological base — because healthy biology is the most cost-effective adaptation available:

| Biological indicator | What to assess | Why it matters for climate |
|---|---|---|
| Organic matter % | Lab test or OM trend | Every 1% OM = ~160,000L/ha additional water-holding |
| Soil aggregate stability | Slake test or visual assessment | Stable aggregates resist both drought and flood erosion |
| Infiltration rate | Timing how fast a set volume of water enters the soil | Determines runoff vs. infiltration during rain events |
| Ground cover % | Walk-over count | Bare soil loses water and structure; covered soil retains both |
| Diversity of enterprises | Count of distinct income sources | Single enterprises have undiversified climate exposure |

**Step 4: Prioritise by cost-impact ratio.**

Work through adaptation options in order of cost-to-impact, lowest cost first:

1. Build OM and soil biology (cover crops, compost, reduced tillage) — highest impact, lowest cost
2. Diversify varieties within existing enterprises — low cost, immediate
3. Diversify enterprises — medium cost and disruption, fundamental resilience
4. Establish physical infrastructure (windbreaks, shade, drainage) — higher cost, targeted
5. Install water capture and storage — significant capital, high impact in right context

**Checkpoint — confirm before finalising:**
- What region and climate zone is this farm in — what does the local climate trend look like?
- What are the primary enterprises, and which is most financially exposed to climate variability?
- What is the current soil OM level, ground cover %, and biological status — has the cheapest adaptation lever been pulled first?

Skipping the biological assessment before recommending infrastructure is the most common mistake in climate adaptation planning — it replaces cheap, durable solutions with expensive ones.

**Output:**
```
FARM CLIMATE RISK ASSESSMENT

Location: [region / climate zone]
Trend: [temperature / precipitation / extreme events summary]

ENTERPRISE RISK PROFILE
Enterprise: [name] — Risk: [High / Medium / Low]
  Primary threat: [drought / heat / flood / frost-shift / pest-disease]
  Exposure window: [season / months]
  Current vulnerability: [specific detail]

BIOLOGICAL FOUNDATION STATUS
Organic matter: [%] — [status: low / adequate / strong]
Aggregate stability: [status from slake test]
Infiltration: [status]
Ground cover: [%]
Enterprise diversity score: [1–5 enterprises]

PRIORITY ADAPTATION ACTIONS
1. [action] — Cost: [Low/Med/High] — Impact: [description]
2. [action] — Cost: [Low/Med/High] — Impact: [description]
3. [action] — Cost: [Low/Med/High] — Impact: [description]

BIOLOGICAL ADAPTATION POTENTIAL
If OM improved from [current]% to [target]%:
  Additional water-holding: [litres/ha]
  Equivalent rainfall buffer: [mm]
  Estimated cost via cover crops: [£/$]

NEXT ACTION: [specific first step]
```

**Next steps:**
- Run **water-resilience** (within this skill) if drought or flood is the highest-ranked risk.
- Run **diversity-as-resilience** (within this skill) if enterprise concentration is the main exposure.
- `/s4ag-soil` — build the biological foundation that underpins every adaptation option.

---

## Water Resilience

*Drought-proofing and flood management strategies, starting with biological options before infrastructure.*

Water is the most common climate stress point for farms. The framework here works in both directions — too little and too much — because the same soil biology improvements that help in drought also reduce flood damage.

**Drought resilience pathway:**

Work through these layers in order. Each layer builds on the one before.

**Layer 1: Build soil water-holding capacity through biology.**

This is the highest-return investment for drought resilience and costs far less than irrigation infrastructure.

| Practice | Water-holding benefit | Timeline |
|---|---|---|
| Increase OM by 1% (30cm depth) | ~160,000L/ha additional retention | 2–5 years |
| Establish continuous ground cover | Reduce evaporation by 30–50% | Immediate |
| Build soil aggregate structure | Infiltration rate increases 5–20x | 1–3 years as fungi rebuild |
| Introduce perennial deep roots | Access subsoil moisture below annual crop root zone | 2–7 years depending on species |
| Reduce tillage | Preserve fungal networks and aggregate stability | Immediate |

**Ingham lens:** Mycorrhizal fungal networks are drought insurance that conventional agronomy does not price. Connected fungal networks can transport water between plant root zones — effectively redistributing soil moisture across a wider area than any individual plant can access. Every fungicide application and every tillage event severs this network. Protecting and rebuilding it costs almost nothing.

**Layer 2: Match water use to water supply.**

| Strategy | Application | Notes |
|---|---|---|
| Match crop choice to rainfall probability | Avoid moisture-hungry crops in dry years | Variety-selection sub-tool for specific options |
| Drip irrigation where irrigation is used | 30–50% water saving vs. overhead | Pairs well with mulch for further savings |
| Mulching | Reduce soil evaporation by 40–70% | Use on high-value crops first |
| Irrigation scheduling by soil moisture monitoring | Avoid over- and under-watering | Basic tensiometers are low-cost |

**Layer 3: Water capture and storage.**

Only after Layers 1 and 2 are in place does additional water infrastructure offer its best return.

| Option | Scale | Cost | Key consideration |
|---|---|---|---|
| Keyline ripping | Farm-scale | Low-Med | Spreads water laterally; must be on contour |
| On-contour swales | Field scale | Med | Requires survey; permanent earthwork |
| Farm dam or pond | Farm-scale | High | Site selection critical; run-off catchment |
| Rainwater tanks | Infrastructure/garden | Low | Limited volume; useful for high-value water |

**Flood and waterlogging resilience:**

Heavy rainfall events and waterlogging are the other edge of water risk. The same biological improvements help here — aggregate stability reduces erosion and runoff; high-OM soils infiltrate faster.

| Flood risk | Biological response | Infrastructure response |
|---|---|---|
| Waterlogging in low areas | Increase OM and biological drainage (deep roots, earthworms) | Tile drainage as a last resort |
| Runoff and topsoil loss | Ground cover 100% of the time; aggregate stability | On-contour earthworks to slow water |
| Gully formation | Establish perennial vegetation in water pathways | Rock check dams, revegetation |
| River or stream flooding | Farm design on higher ground; riparian buffer plantings | No conventional engineering solution pays back |

**Checkpoint — confirm before finalising:**
- Is the primary threat drought, waterlogging, or both — and what enterprise is most exposed?
- What is the current soil OM and infiltration rate — what biological headroom is available before infrastructure is considered?
- Is this a crisis response (drought is happening now) or planning ahead? The answer determines whether to lead with immediate or medium-term actions.

A plan that recommends irrigation infrastructure without first addressing soil biology investment almost always overspends — in many cases, building OM solves the problem the infrastructure was being bought to solve.

**Output:**
```
WATER RESILIENCE PLAN

Primary risk: [drought / flood / both]
Most exposed enterprise: [enterprise name]
Current soil OM: [%]    Infiltration: [status]

BIOLOGICAL ACTIONS (do first)
1. [action] — Timeline: [timeline] — Est. cost: [cost]
2. [action] — Timeline: [timeline] — Est. cost: [cost]
3. [action] — Timeline: [timeline] — Est. cost: [cost]

Expected water-holding gain from biological actions:
  OM target: [%]   Additional retention: [L/ha]   Equivalent rainfall: [mm]

MANAGEMENT ACTIONS
[action]: [specific change] — Timeline: [when] — Cost: [cost]

INFRASTRUCTURE (if biological approach insufficient)
[option]: [description] — Cost: [£/$] — Expected benefit: [benefit]

IMMEDIATE ACTIONS (this season)
- [specific step]
- [specific step]
```

**Next steps:**
- `/s4ag-water` — irrigation scheduling, water harvesting, and drainage in detail.
- `/s4ag-earthworks` — contour earthworks and water capture infrastructure design.
- `/s4ag-soil` — build the OM and biology that is the cheapest water insurance available.

---

## Diversity as Resilience

*Enterprise and species diversity as a hedge against climate variability — reducing the risk of a single bad year wiping out the whole operation.*

A farm that depends on one enterprise in one climate window has undiversified climate exposure. Diversification is an insurance strategy — it rarely maximises returns in good years, but it prevents catastrophic losses in bad ones.

**Enterprise diversification logic:**

Not all diversification is equal. The goal is diversification across climate windows, water requirements, and price cycles — not just adding enterprises for their own sake.

| Diversification type | What it protects against | Examples |
|---|---|---|
| Seasonal spread | No single weather event takes all income | Mix spring, summer, and autumn enterprises |
| Water-requirement spread | Drought or flood hits some enterprises, not all | Mix deep-rooted perennials with shallow annuals |
| Price cycle spread | Market price crash in one commodity | Mix fresh produce, stored crops, livestock |
| Enterprise type | Single input (labour, feed, water) shortage | Mix crop and livestock; mix pasture and annuals |
| Perennial vs. annual | Annuals fail in extreme years; perennials persist | Introduce orchard, pasture, or food forest component |

**Worked examples:**

*Scenario 1: Grain farm in a drying region.*
Single enterprise — winter wheat. Risk: drought in the critical late spring period. Diversification pathway: introduce a drought-tolerant legume (lupins, chickpeas) into rotation; reduce the proportion of wheat by 25%; introduce a silvopasture component to generate income from land in drought years.

*Scenario 2: Market garden in a high-temperature zone.*
Single climate window — cool-season vegetables in spring and autumn. Risk: compressed spring and autumn windows as summers get hotter. Diversification pathway: introduce summer-tolerant varieties; add perennial fruits and herbs that don't require the cool windows; introduce storage crops (garlic, onions, potatoes) that decouple production from the fresh market window.

*Scenario 3: Dairy farm in a flood-risk area.*
Single enterprise — irrigated dairy. Risk: flooding of low-lying pasture blocks, disruption to irrigation infrastructure. Diversification pathway: move lower-risk enterprises to the flood-prone blocks (willow, osier, wetland plants); develop a dryland enterprise on high ground; reduce reliance on irrigated pasture over time.

**Species diversity within enterprises:**

Within any enterprise, planting or growing multiple varieties reduces exposure to the specific vulnerabilities of any single variety.

| Enterprise | Conventional approach | Climate-resilient approach |
|---|---|---|
| Orchards | Single commercial variety | 3–5 varieties with staggered flowering (frost risk spread) |
| Grain | Single high-yield variety | Heritage and modern varieties; 2–3 to spread risk |
| Pasture | Ryegrass-clover | 8–12 species mix including drought-tolerant forbs |
| Vegetables | Commercial F1 varieties | Supplement with open-pollinated and heritage varieties adapted to place |

**Food web perspective on diversity:**
Diverse plant systems feed diverse microbial communities (Lowenfels/Lewis). Diverse food webs maintain function under stress — they are more resilient to temperature extremes, drought, and soil disturbance than simplified biological systems. Species diversity and soil biological diversity are linked: the more plant species, the more microbial diversity, the more buffered the system.

**Checkpoint — confirm before finalising:**
- How many distinct income-generating enterprises does the farm currently have — what is the concentration risk?
- What is the key climate vulnerability of the dominant enterprise — and which diversification type addresses it?
- Is the farmer in a position to change enterprise mix this season, or is this medium-term planning?

Recommending enterprise diversification without understanding the farmer's capital, labour, and market access constraints produces advice that cannot be acted on.

**Output:**
```
DIVERSITY RESILIENCE ASSESSMENT

Current enterprise concentration:
  Primary enterprise: [name] — % of revenue: [%]
  Secondary enterprise: [name] — % of revenue: [%]
  Concentration risk: [High / Medium / Low]

Key climate vulnerability of dominant enterprise:
  [vulnerability description]
  Climate window: [months at risk]

DIVERSIFICATION PRIORITIES
Priority 1: [diversification action]
  Addresses: [risk type]
  Timeline: [when feasible]
  Estimated cost / complexity: [assessment]

Priority 2: [diversification action]
  Addresses: [risk type]
  Timeline: [when feasible]
  Estimated cost / complexity: [assessment]

SPECIES DIVERSITY WITHIN ENTERPRISES
Enterprise: [name]
  Current variety count: [number]
  Recommended variety spread: [recommendation]
  Climate rationale: [why this helps]

TRANSITION STEP THIS SEASON
[one concrete action to start diversification now]
```

**Next steps:**
- Run **variety-selection** (within this skill) to populate the diversification plan with specific varieties.
- `/s4ag-agroforestry` — perennial tree and shrub components are among the most durable climate-resilience investments.
- `/s4ag-finance` — diversification has a financial profile; model the income stability benefit against the transition cost.

---

## Infrastructure Adaptation

*Polytunnels, windbreaks, shade structures, and drainage improvements as physical climate buffers — when to invest and how to design them.*

Physical infrastructure is the right answer when biological and management options have been exhausted or are insufficient for the specific risk. The sequence matters: infrastructure built on a poor biological foundation underperforms and costs more to maintain.

**Decision framework for infrastructure investment:**

Before committing to any structure, confirm:
1. Has OM been built to its realistic maximum through cover crops and compost? (3–5 years of consistent practice)
2. Have variety selections been reviewed for climate tolerance? (Immediate, low cost)
3. Have enterprise and species diversity options been explored? (1–3 years to implement)

If yes to all three, infrastructure investment is likely to deliver good returns.

**Windbreaks:**

| Design element | Specification | Climate function |
|---|---|---|
| Porosity | 40–50% — not a solid barrier | Permeable windbreaks reduce wind speed over 10–15x their height; solid barriers create turbulence |
| Species | Mixed native species — deciduous and evergreen | Year-round protection; ecological function; habitat value |
| Width | Minimum 3 rows; 5+ rows more effective | Width determines depth of protection zone |
| Orientation | Perpendicular to prevailing wind | Site-specific — assess prevailing wind direction first |
| Expected benefit | Reduce wind speed 50–80% for 10–15H downwind | Direct crop benefit: reduced transpiration, reduced physical damage, microclimate warmer by 2–5°C |

**Polytunnels and low tunnels:**

| Type | Capital cost | Climate benefit | Best use |
|---|---|---|---|
| Permanent polytunnel | High | Extends season by 6–8 weeks each end; protects from extreme events | High-value crops; year-round production |
| Temporary low tunnels | Low | 2–4°C frost protection; extends spring and autumn windows | Cost-effective for medium-value crops |
| Shade cloth | Low-Med | Reduces heat stress; extends cool-season crop window | Brassicas and salad in hot climates |
| Frost fleece | Very low | 2–3°C protection; critical at blossom time in orchards | Orchards; early transplants |

**Shade and heat management:**

In warming climates, summer heat is increasingly the limiting factor for cool-season crops.

| Strategy | Application | Cost |
|---|---|---|
| Shade cloth (30–50%) | Over polytunnel or outdoor crops | Low |
| Companion tree planting | Deciduous trees on west or south-west aspect | Free over time; 5–10 years to useful shade |
| White or reflective mulch | Reduce soil surface temperature | Low |
| Evening irrigation scheduling | Avoid heat stress during hottest part of day | Management change; no capital |

**Drainage infrastructure:**

Waterlogging is often faster and cheaper to address through biological means (deep-rooted cover crops, OM building, earthworm habitat) than through tile drainage. Install drainage only after confirming that biological drainage has been tried and is insufficient.

| Option | When appropriate | Notes |
|---|---|---|
| On-contour swales | Surface water movement; gentle slopes | Captures and slows water; requires earthworks |
| Tile drainage | Persistent subsoil waterlogging on productive land | Capital-intensive; disrupts biology; justified when biological approach is insufficient |
| Open ditches | Perimeter drainage; collecting water from swales | Maintenance required; low capital |
| Riparian buffer establishment | Stream bank erosion; flood damage | Double function: protection and habitat |

**Checkpoint — confirm before finalising:**
- Has the biological foundation (OM, cover crops, diversity) been addressed first — or is this infrastructure filling a gap that biology could fill more cheaply?
- What is the specific climate threat this infrastructure addresses, and what is the quantified benefit expected?
- What are the capital budget and payback timeline requirements — does the infrastructure pencil out financially?

Infrastructure that replaces biological investment rather than supplementing it becomes a recurring cost with no compounding return. Biology compounds; infrastructure depreciates.

**Output:**
```
INFRASTRUCTURE ADAPTATION PLAN

Biological foundation status: [OM / cover crop / diversity — done / not yet]
Climate threat being addressed: [specific threat]

RECOMMENDED INFRASTRUCTURE
Type: [windbreak / polytunnel / shade / drainage / other]
Specification: [key design parameters]
Estimated capital cost: [£/$]
Annual maintenance: [£/$]
Expected climate benefit: [description]
Payback timeline: [years]

SEQUENCING
Year 1: [action — biological or low-cost first]
Year 2: [action]
Year 3: [infrastructure investment if biological phase is complete]

WHAT NOT TO SKIP
[biological actions that must happen before or alongside infrastructure for it to perform]
```

**Next steps:**
- `/s4ag-earthworks` — contour earthworks, swale design, and water capture infrastructure.
- `/s4ag-biodiversity` — windbreaks and buffer zones as habitat infrastructure with dual climate function.
- `/s4ag-water` — irrigation system design and water harvesting to complement physical climate adaptation.

---

## Variety Selection

*Choosing climate-adapted varieties and species for shifting conditions — heat tolerance, drought adaptation, frost resilience, and disease resistance in a changing climate.*

Variety selection is the lowest-cost, most immediate climate adaptation available. Seeds are cheap relative to almost any other input — the right variety in the wrong year beats the wrong variety in the right year every time.

**Framework for climate-adapted variety selection:**

**1. Identify your climate analogue.**

The most practical approach to variety selection for a warming or drying climate: find the region that currently has the climate your region is projected to have in 20–30 years. Varieties adapted to that climate are your best candidates.

- Use national or regional climate projection maps to identify your 2040–2050 analogue.
- Look for traditional or heritage varieties from that region — they have been selected by natural conditions, not by input-intensive breeding programmes.
- Contact seed companies, heritage seed networks, or growers in that analogue region.

**2. Match variety traits to risk type:**

| Climate risk | Trait to select for | Notes |
|---|---|---|
| Heat stress | Heat tolerance at flowering; thermotolerance | Critical stage: heat during pollination causes yield failure |
| Drought | Deep root development; drought-escape timing; low transpiration | Early-maturing varieties "escape" late-season drought |
| Late frost shift | Late-flowering varieties (orchards); frost-tolerant blossom | Blossom timing is the critical vulnerability in tree fruits |
| Early frost shift | Short-season varieties that mature before first frost | Check days-to-maturity against your frost-free window |
| Increased humidity / disease | Disease-resistant varieties; airflow design | High disease pressure invalidates variety performance data |

**3. Specific guidance by enterprise:**

**Annual vegetables:**
- Move toward open-pollinated and heritage varieties with local adaptation — they have phenotypic plasticity that F1 hybrids bred for uniformity lack.
- Trial heat-tolerant brassicas (calabrese varieties, kale over cabbage for summer production).
- For tomatoes in warming climates: look for indeterminate varieties bred in Mediterranean or subtropical environments.

**Pasture and forage:**
- Replace ryegrass-dominant swards with diverse mixes including plantain, chicory, yarrow, clover species, and drought-tolerant grasses.
- Diverse swards maintain productivity 60–80% of peak yield under drought; ryegrass monocultures lose productivity rapidly below a moisture threshold.
- Chicory and plantain provide deep taproot access to subsoil moisture — critical drought bridge.

**Tree fruits and orchards:**
- The most critical climate trait for orchards: blossom timing relative to late frost risk.
- Select late-flowering varieties where late frosts are increasing (warmer autumns advance bud break but frosts remain).
- Alternatively: diversify across early, mid, and late varieties to spread risk across the blossom window.
- Seek rootstocks with tolerance for both drought stress and waterlogging — climate variability means both events in the same region.

**Grain:**
- Heritage and landrace varieties adapted to low-input, variable conditions frequently outperform modern varieties when inputs are reduced and stress events occur.
- Emmer, einkorn, and spelt are significantly more drought-tolerant than modern bread wheat.
- Composite cross populations (CCPs) — genetically diverse wheat populations — maintain yield stability across variable seasons better than uniform modern varieties.

**4. Source locally adapted seed where possible.**

Nabhan's research is directly applicable here: seed saved from plants that have experienced your local conditions carries epigenetic advantages for those conditions. Even if the variety is not optimal, locally grown seed from a farm in a similar climate will outperform the same variety grown and harvested in a different climate.

**Checkpoint — confirm before finalising:**
- What is the primary climate threat affecting the enterprises in question — heat, drought, frost timing, or disease?
- Is conventional (commercial) variety sourcing acceptable, or is the farmer seeking heritage or open-pollinated alternatives?
- What is the soil health status — variety performance is highly dependent on biology; a stressed soil penalises every variety.

Recommending drought-tolerant varieties without addressing the biological foundation is like recommending drought-tolerant tyres on a car with no engine — the constraint is elsewhere.

**Output:**
```
VARIETY SELECTION RECOMMENDATIONS

Enterprise: [enterprise type]
Primary climate risk: [heat / drought / frost-shift / disease / combined]
Climate analogue region: [target region for variety sourcing]

RECOMMENDED VARIETIES
Variety: [name]
  Trait: [specific climate adaptation]
  Source: [where to obtain]
  Notes: [any caveats]

Variety: [name]
  Trait: [specific climate adaptation]
  Source: [where to obtain]
  Notes: [any caveats]

VARIETIES TO MOVE AWAY FROM
[variety or type]: [reason — climate vulnerability]

PASTURE MIX RECOMMENDATION (if applicable)
Species mix: [list]
  Drought bridge: [species]
  Deep root component: [species]
  Diversity target: [minimum species count]

SEED SOURCING APPROACH
[local / heritage network / commercial climate-adapted / trial several]

SOIL HEALTH NOTE
[Current soil status and its effect on any variety's performance — what needs to happen biologically for these varieties to perform]
```

**Next steps:**
- `/s4ag-seeds` — save seed from plants that perform well in stress years to build locally adapted varieties over time.
- Run **diversity-as-resilience** (within this skill) to combine variety diversity with enterprise diversity.
- `/s4ag-soil` — soil biology determines how well any variety performs; address the biological base alongside variety change.