#include <bits/stdc++.h>
using namespace std;

#define st first
#define nd second
#define mp make_pair
#define pb push_back
#define cl(x, v) memset((x), (v), sizeof(x))
#define db(x) cerr << #x << " == " << x << endl
#define dbs(x) cerr << x << endl
#define _ << ", " <<
#define gcd(x, y) __gcd((x), (y))

typedef long long ll;
typedef long double ld;
typedef pair<int, int> pii;
typedef pair<int, pii> piii;
typedef pair<ll, ll> pll;
typedef vector<int> vi;
typedef vector<vi> vii;

const ld EPS = 1e-9, PI = acos(-1.);
const ll LINF = 0x3f3f3f3f3f3f3f3f, LMOD = 1011112131415161719ll;
const int INF = 0x3f3f3f3f, MOD = 1e9+7;
const int N = 5e3+5;
const int K = 20;
const int M = K+5;

vi adj[N];
int vis[N], h[N], anc[N][M];
int n, d, a, b, w, m;
ll wei[N], sum[N], dp[N];

void dfs (int u) {
    vis[u] = 1;
    for (auto v : adj[u]) if (!vis[v]) {
        h[v] = h[u]+1;
        anc[v][0] = u;
        dfs(v);
    }
}

void dfstwo (int u) {
    vis[u] = 1;
    for (auto v : adj[u]) if (!vis[v]) {
        dfstwo(v);
        sum[u] += sum[v];
    }
}

void build () {
    anc[1][0] = 1;
    dfs(1);
    for (int j = 1; j <= K; j++) for (int i = 1; i <= n; i++)
        anc[i][j] = anc[anc[i][j-1]][j-1];
}

int lca (int u, int v) {
    if (h[u] < h[v]) swap(u, v);
    for (int j = 20; j >= 0; j--) if (h[anc[u][j]] >= h[v]) u = anc[u][j];
    if (u == v) return u;
    for (int j = 20; j >= 0; j--) if (anc[u][j] != anc[v][j]) u = anc[u][j], v = anc[v][j];
    return anc[u][0];
}


int main () {
    scanf("%d%d", &n, &d);

    for (int i = 0; i < n-1; i++) {
        scanf("%d%d", &a, &b);
        adj[a].pb(b);
        adj[b].pb(a);
    }

    build();

    scanf("%d", &m);
    for (int i = 1; i <= m; i++) {
        scanf("%d%d", &a, &b);
        wei[a] = b;
    }

    scanf("%d", &m);
    while (m--) {
        scanf("%d%d%d", &a, &b, &w);
        sum[a] += w;
        sum[b] += w;
        sum[lca(a, b)] -= w;
    }

    cl(vis, 0);
    dfstwo(1);

    db(sum[4]);
    db(sum[6]);
    for (int i = 1; i <= n; i++) if (wei[i]) {
        for (int j = N-1; j >= wei[i]; j--) {
            dp[j] = max(dp[j], dp[j-wei[i]] + sum[i]);
        }
    }

    for (int i = 1; i <= n; i++) printf("sum[%d] = %lld\n", i, sum[i]);

    ll ans = 0;
    for (int i = 0; i <= d; i++) {
        ans = max(ans, dp[i]);
        printf("dp[%d] = %lld\n", i, dp[i]);
    }

    printf("%lld\n", ans);

    return 0;
}