Introduction to Supplies

The Supplies module allows you to manage inventory of fertilizers, agrochemicals, seeds, and other materials your farm uses, with complete traceability from purchase to field consumption.

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The Agricultural Inventory Problem

Farms handle dozens of different products: fertilizers, fungicides, insecticides, herbicides, packaging materials, fuels. Without a control system:

• Surprise stockouts: You run out of a critical product at the worst time
• Overstock: Capital tied up in products that expire before use
• Unknown costs: Don’t know actual application cost per hectare
• Undetected losses: Differences between theoretical and physical inventory

The Arlo Approach

Arlo implements a perpetual inventory system with:

1. Warehouses: Physical storage locations
2. Supply catalog: Products with purchase and consumption units
3. Movements: Entries (purchases) and exits (consumption)
4. WAVCO costing: Automatic weighted average cost

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Key Concept: WAVCO

WAVCO (Weighted Average Cost) is the costing method Arlo uses to value inventory.

How does it work?

Every time you purchase a product, the system recalculates the average cost:

Example: NPK Fertilizer

Purchase 1: 100 kg at $10/kg = $1,000
  → Average cost: $10/kg

Purchase 2: 50 kg at $12/kg = $600
  → Total inventory: 150 kg
  → Total cost: $1,600
  → New average cost: $1,600 / 150 = $10.67/kg

Exit: 30 kg for application
  → Exit cost: 30 × $10.67 = $320
  → Remaining inventory: 120 kg at $10.67/kg

Why WAVCO?

• Simple: No need to track individual lots
• Realistic: Cost reflects all purchases, not just first or last
• Standard: Method accepted by international accounting standards
• Automatic: Arlo does the calculation for you

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Module Structure

Configuration

Component	Purpose
Warehouses	Storage locations (central warehouse, field warehouse, etc.)
Providers	Companies that sell you supplies
Catalog	Products with units and conversions

Movements

Component	Purpose
Entries	Record purchases and receive inventory
Exits	Record field consumption
Rebalancing	Adjustments for inventory differences

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Purchase vs. Consumption Units

An important concept in Arlo is the distinction between:

Purchase unit

How you buy the product from the provider.

• Example: 50 kg bags, gallons, 200 L drums

Consumption unit

How you use the product in the field.

• Example: Kilograms, liters, grams

Conversion factor

When creating a supply, you define the conversion:

Supply: Triple 15 Fertilizer
- Purchase unit: Bag
- Consumption unit: Kilogram
- Conversion factor: 1 bag = 50 kg

When you buy 10 bags:
- Entry recorded: 10 bags × $500 = $5,000
- System inventory: 500 kg at $10/kg

When you use 25 kg:
- Exit recorded: 25 kg
- Exit cost: 25 × $10 = $250

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Link with Field Tasks

A powerful feature is linking inventory exits with field tasks.

Example

Task: Fertilization - North Lot
  - Contractor: Garcia
  - Quantity: 100 trees

Linked supply exit:
  - Product: NPK Fertilizer
  - Quantity: 50 kg
  - Linked to: Task "Fertilization - North Lot"

This allows:

• Calculate total task cost (labor + supplies)
• Know how much supply was used per tree/hectare
• Detect deviations in expected consumption

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Next Steps

1. Configure warehouses - Define storage locations
2. Register providers - Your supply sources
3. Create the catalog - Products with units and conversions
4. Record your first entry - Start controlling inventory